Friday, November 5, 2010

Como funciona um diferencial

Não subestime os mais velhos...

Procurando uma imagem sobre o funcionamento de um diferencial, acabei encontrando esse vídeo, de 1937. Não se deixe surpreender pela data. O vídeo é sensacional, incrivelmente didático. Fico imaginando o que os criadores dele fariam com os recursos de hoje.

Alguns acharam ridículas as sequências com as motos e as pessoas correndo no final, mas pense nisso no contexto da época, sem animações computadorizadas ou coisa do tipo, e o criador conseguiu ilustrar muito bem a necessidade e o funcionamento do diferencial com ele.

Thursday, November 4, 2010

Counterinsurgency: After smart weapons, smart soldiers

After smart weapons, smart soldiers

REBELLION is as old as authority itself, and so therefore is the business of putting it down. Nearly 2,000 years ago Jewish militants—known as Zealots, hence the English word—took up arms against the world's greatest power and terrorised those deemed collaborators. The Romans dealt with the revolt in Palestine in familiar fashion, laying waste any town that resisted, prompting many to commit suicide rather than suffer capture and, in 70AD, destroying the great Temple in Jerusalem and taking its treasures. “While the holy house was on fire,” records Josephus, “everything was plundered that came to hand, and ten thousand of those that were caught were slain...children and old men, and profane persons and priests, were all slain in the same manner.”

Modern Western armies cannot, as the Romans did, make a wasteland and call it peace. Modern wars are complex affairs conducted “among the people” and, as Sir Richard Dannatt, head of the British army, put it recently, “in the spotlight of the media and the shadow of international lawyers”. In Iraq in the 1920s, Britain's air force pioneered the use of “air policing” to put down rebellious tribesmen on the cheap; today the use of air power often carries big political costs. The greater the accuracy of modern weapons, the louder the outcry when they nonetheless kill or wound civilians. And the wider the reach of the internet, the bigger the impact of propaganda videos showing insurgent attacks against Western forces, regardless of civilian casualties. The British who fought the Mahdist religious rebels in Sudan in the 19th century had no need to worry about provoking attacks in London; today such a campaign would be seen as another front in the jihadagainst the West.

Many others, though, regard today's conflicts as variations on age-old irregular warfare, not least Mao Zedong's “protracted war” in China, the Spanish guerrilla attacks against Napoleon's forces in Spain, or even America's war of independence from Britain. Whatever the definition, “small wars” can have big effects. In the past six decades the British have been driven out of Palestine, the French from Algeria, the Americans (and French) from Vietnam, the Russians from Afghanistan and the Israelis from Lebanon.

Can America and its Western allies avoid similar humiliation in Iraq and Afghanistan? Martin van Creveld, an Israeli military historian, argues that insurgencies have been almost impossible to defeat ever since Nazi Germany failed to suppress Josip Broz Tito's partisans in Yugoslavia. Winning such wars requires one of two tactics: extreme restraint and patience, as shown by the British over nearly 38 years in Northern Ireland; or extreme brutality, as shown by Syria in 1982 when the army destroyed much of Hama, a stronghold of Islamist rebels, killing at least 10,000 people. Any other method, says Mr van Creveld, risks being too harsh to win the support of the population but not harsh enough to cow it into submission.

This rule is too stark. Experts point to successes such as the end of the insurgency in El Salvador, the collapse of the Shining Path rebels in Peru, the end of the civil wars in Mozambique and Angola, the demise of the Red Brigades in Italy and of the Red Army Faction in Germany. Much of this debate revolves around the meaning of victory and defeat, as well as the definition of counter-insurgency, civil war, counter-terrorism and so on. One school of thought holds that America's forces had largely defeated the Vietcong in Vietnam when its politicians lost the will to stop North Vietnam's conventional army from overrunning the south. That is to miss the point: in counter-insurgency one side can win every battle, yet lose the war.


Such arguments are a hot topic at Western military colleges, especially in America. More has been written on counter-insurgency in the past four years than in the previous four decades. The study of small wars was largely abandoned by the United States army in the 1970s as commanders promised “no more Vietnams” and concentrated instead on how to defeat the massed Soviet armies. America's humiliating retreats from Lebanon in 1983 and Somalia in 1994 convinced many Americans that, as Colin Powell, a former general (and later secretary of state), once put it, America should not get involved in “half-hearted warfare for half-baked reasons”. The swift ejection of Iraq's forces from Kuwait in 1991 reinforced such beliefs. Counter-insurgency became a secondary task undertaken mainly by American special forces, which sometimes offered training to friendly governments.

Given the difficulties in Iraq and Afghanistan, American officers are relearning the history of their own interventions in Latin America and, more important, the lessons of British imperial policing. Why, American experts asked, did Britain succeed against communist revolutionaries in Malaya in the 1950s, whereas America failed to defeat the communists in Vietnam in the 1960s and 1970s?

In his 2002 book “Learning to Eat Soup with a Knife” (a title drawn from T.E. Lawrence's “Seven Pillars of Wisdom”, describing the messiness of waging “war upon rebellion”), John Nagl, an American lieutenant-colonel, concluded that British soldiers were better than the Americans at learning from their mistakes. General Sir Gerald Templer, the British high commissioner in Malaya, argued that “the shooting side of the business” was only a minor part of the campaign. Coining a phrase, he suggested that the solution “lies not in pouring more troops into the jungle, but in the hearts and minds of the people”. In contrast, says Colonel Nagl, the Americans in Vietnam remained wedded to “unrestrained and uncontrolled firepower”, despite some work with small units that were deployed in border villages and civil-military reconstruction projects.

British officers are less impressed, saying their predecessors often repeated their errors. During the troubles in Northern Ireland, the arrival of British troops in 1969 was at first welcomed by Roman Catholics. But the army's heavy-handed methods, such as large cordon-and-search operations and the shooting of 13 civilians on Bloody Sunday in 1972, pushed many Catholics into the arms of the Provisional Irish Republican Army.

In any event, the American army and marines have produced a new counter-insurgency manual. One of its authors, General David Petraeus, is now in charge of the “surge” in Iraq. It may be too late to turn Iraq round, and Afghanistan could slide into greater violence. But the manual offers some comfort: it says counter-insurgency operations “usually begin poorly”, and the way to success is for an army to become a good “learning organisation”.

According to Mao's well-worn dictum, guerrillas must be like fish swimming in the “water” of the general population. T.E. Lawrence, helping to stir up the Arab revolt against Turkish rule during the first world war, described regular armies as plants, “immobile, firm-rooted, nourished through long stems to the head”. Guerrillas, on the other hand, were like “a vapour”. A soldier, he said, was “helpless without a target, owning only what he sat on, and subjugating only what, by order, he could poke his rifle at”.

Western armies have unsurpassed firepower, mobility and surveillance technology. Guerrillas' main weapons are agility, surprise, the support of at least some sections of the population and, above all, time. The warren of Iraqi streets and the fortified compounds of Afghanistan compensate for the insurgents' technological shortcomings. The manual, however, attempts to change the army mindset: in fighting an enemy “among the people”, it says, the central objective is not to destroy the enemy but to secure the allegiance of the citizenry. All strands of a campaign—military, economic and political—have to be strongly entwined.

Much of this thinking is drawn from the British experience in Malaya, but conditions today are vastly different. In Templer's day, securing “hearts and minds” did not mean just acting with kindness to win the people over; it also included coercion. Hundreds of thousands of ethnic Chinese, among whom the insurgents mainly operated, were uprooted and moved into guarded camps known as “new villages”, where they were offered land. If the British could not find the fish, they resorted to removing the water.

They also sought to starve insurgents by restricting supplies of food to the population. In some areas rations of rice were handed out in cooked form so they would spoil before they could reach fighters in the jungle. Such measures are unthinkable today. Even the building of separation walls to reduce sectarian killings in Baghdad arouses Iraqi opposition. Checkpoints and curfews now have limited impact.

Templer was both the civil and the military boss. He emphasised policing rather than military operations, and the use of indigenous forces. The majority Malay population largely supported the British. In a peninsula, the borders were relatively well controlled and the rebels had few external sources of support. Above all, the British had full sovereignty over Malaya. They could undercut the insurgents' claim to be fighting colonialism by guaranteeing equal rights, and by promising—and eventually granting—independence.

By contrast, the borders of Iraq and Afghanistan are permeable. Some neighbours are either hostile to the West (Iran) or unable to remove insurgent havens (Pakistan). The powers of America's Coalition Provisional Authority in Iraq lasted a year, long enough for America to make egregious errors, such as disbanding the Iraqi army and removing former Baathists, but not long enough to correct them.


In Iraq the American effort is split between the military operations overseen by the generals and the civil and political work conducted by the embassy. In Afghanistan leadership is even more divided. There are two separate Western military commands—the NATO-led International Security Assistance Force, which provides the bulk of the troops, and the American-led Operation Enduring Freedom, which concentrates on hunting “high-value targets”. Alongside these are a myriad of poorly co-ordinated reconstruction agencies.

Coalitions add further complications. Britain, America's only ally of any military significance in Iraq, is slowly leaving. And in Afghanistan, where boots on the ground are in short supply, NATO is wobbly. Many allies refuse to join a fight that has been waged mainly by American, British and Canadian forces, and several are under domestic pressure to bring their troops home. Overt colonialism has died, and with it have gone the large colonial armies. Counter-insurgency requires large numbers of security forces. But the West's all-volunteer forces have progressively cut expensive manpower in favour of technology. They have become infinitely better at finding and destroying things; but the best source of intelligence on the ground is often the soldier on the street with his “Eyeball mark-1”.

Nationalist and pan-Islamic sentiments are much stronger than in the past. Information technology has helped jihadists spread the “single narrative” that Muslims everywhere are under attack, a contention reinforced by America's rhetoric about the “global war on terror”. The internet provides a new and unassailable sanctuary from which to propagandise, organise and share tactics.

Still, the generals plead for more time. They point to Iraq's Anbar province, where Sunni tribes are turning against al-Qaeda. In Afghanistan, says Britain's General Dannatt, “strategic patience” is essential. American officers quote internal studies showing that it takes nine years on average (and often much longer) to defeat insurgencies. Yet perseverance is no guarantee of victory; many campaigns have taken as long, if not longer, to lose.

A growing body of opinion, both in the Pentagon and outside, has concluded that insurrections are best fought indirectly, through local allies. “It is extremely difficult for Western powers to defeat insurgencies in foreign countries in modern times,” says Max Boot, author of “War Made New” (2006). “At the same time, there are very few instances of insurgencies overthrowing a local government. The problem is that Western armies lose the will to maintain imperial domination.” Western forces always have the option of going home; for local governments, though, fighting insurgents is a matter of survival.

A better model than Malaya, argues Mr Boot, is the end of the Marxist insurrection in El Salvador in 1992. American forces did not lead the fighting. Instead, a small contingent of under 100 advisers from America's special forces helped the democratising government reorganise its army and avoid the fate of nearby Nicaragua, which fell to the Sandinistas in 1979. This approach has its own difficulties: America's reputation was tarnished by right-wing Salvadorean death-squads. In the end it was external political factors—the demise of the Sandinistas in Nicaragua, partly caused by an American-backed insurgency, and the collapse of the Soviet Union—that helped bring about a settlement and the incorporation of the guerrillas into a new-found democracy.

David Kilcullen, an Australian colonel and General Petraeus's main adviser on counter-insurgency, says fighting insurgencies in other people's countries is hard. “Running Baghdad is not like trying to police New York City; it's like the Iraqi police trying to run New York City.” Tellingly, he says, Indonesian forces successfully put down an insurrection by the Islamist Darul Islam movement in the 1950s and early 1960s, but could not quell the resistance to their annexation of East Timor.

The dilemma for Western forces in Iraq and Afghanistan is that, though they may lack the wherewithal to win, the national governments they seek to help are unable to stand up on their own. At best, Western armies can create the political space to build viable governments. But this has proved difficult enough even where the fighting has stopped and the main political forces have been co-operative (or at least acquiescent)—as in Bosnia and East Timor. It may be impossible under sustained fire.


Although most armies have now relearnt the limits of force and the importance of the “comprehensive approach”, commanders complain that other branches of government have not. In a recent article, General Peter Chiarelli, an adviser to Robert Gates, America's secretary of defence, says more money has to be spent not on the Pentagon but on the “non-kinetic aspects of our national power”. He recommends building up the “minuscule” State Department and USAIDdevelopment agency (so small it is “little more than a contracting agency”), and reviving the United States Information Agency.

As the American army expands, some thinkers, such as Colonel Nagl, say it needs not just more soldiers—nor even linguists, civil-affairs officers and engineers—but a fully fledged 20,000-strong corps of advisers that will train and “embed” themselves with allied forces around the world. The idea makes army commanders blanch, but they do not question the underlying assumption. Insurgencies may be the face of war for the West in the years ahead. Even if America cannot imagine fighting another Iraq or Afghanistan, extremists round the world have seen mighty America's vulnerability to the rocket-propelled grenade, the AK-47 and the suicide-bomber.

The Economist

Wednesday, November 3, 2010

Ineficácia Militar Árabe

Ineficácia militar árabe

Os árabes são o povo que talvez mais consistentemente envolveu-se em conflitos armados e mais consistentemente sofreu derrotas. Nos conflitos modernos isso é uma constante. As vitórias, até o século X, devem-se muito mais ao fato de enfrentarem inimigos enfraquecidos e pelo seu conhecimento do deserto do que a qualquer outra coisa.

Um dos livros mais interessantes sobre história e estratégia militar que li nos últimos tempos busca responder esta questão. O livro é o "Arabs at War, Millitary Effectiveness, 1948-1991", Kenneth M. Pollack.

Desde a segunda guerra mundial, o Oriente Médio foi provavelmente a região mais conturbada, quase todos os conflitos com envolvimento dos árabes em alguma escala, e em todos eles a ineficácia surpreende. Alguém pode observar o histórico militar de Egito, Iraque, Arábia Saudita, Jordânia, Líbia e Síria, em combate com israelenses, europeus, americanos, persas, curdos, africanos, e até entre eles mesmos, e é sempre impressionante como atuam com ineficácia de maneira bem consistente, independente do adversário e das condições.

Dois exemplos extremos tanto em caso de vitória quanto derrota são a Síria na Guerra do Yom Kipur, e o Iraque no conflito com o Irã, e o final decisivo do conflito entre Líbia e Chade no norte do país em 1987-1988.

A ofensiva da Síria contra as forças israelenses no Golan em 1973 é comparável em disparidade à Operação Bagration pela URSS contra as tropas da Alemanha na Bielorússia durante a segunda guerra mundial. Um exército de veteranos defendendo linhas bem estabelecidas e fortificadas contra uma ofensiva massiva de surpresa com grande superioridade numérica. Os soviéticos tiveram sua maior vitória, enquanto os sírios tiveram sua pior derrota em condições de superioridade similares.

O Iraque passou praticamente uma década enfrentando o Irã com grande superioridade numérica e tecnológica, mas só conseguiu uma vitória em 1988 usando armas químicas em larga escala, matando cerca de 20,000 soldados iranianos, quase 1/5 das forças, e criando forças locais com disparidade de até 30 para 1 em relação aos iranianos.

No Chade, depois que os líbios perderam seu apoio entre os dissidentes chadianos, ainda contavam com decisiva vantagem numérica e tecnológica. Os chadianos não tinham tanques, blindados, aviões e artilharia, e não sabiam usar bem o pouco equipamento de infantaria que tinham. O único armamento pesado e transporte de que dispunham eram pick-ups Toyota com mísseis antitanque Milan fornecidos pela França na última hora, e confiavam na força aérea francesa e stingers fornecidos pelos EUA para defender-se dos líbios. Mesmo com a vantagem em todos os aspectos, os líbios sofreram uma derrota completa no norte do país. A principal base foi abandonada com muito equipamento ainda funcionando, soldados líbios morriam ao fugir pelos próprios campos minados, e a força aérea líbia tinha de destruir o próprio equipamento para evitar que fosse utilizado pelo inimigo.

Ou seja, independente do oponente e de vitória ou derrota, as forças árabes sempre atuam com muito menos eficácia do que esperado para seu número, equipamento e posição. Qual o real motivo disso?

Eu nunca havia pensado muito a fundo no assunto, e por conhecer melhor o conflito árabe-israelense, aceitava a explicação de cada guerra em particular, sem me preocupar muito nisso como característica dominante. Agora li um livro que trata especificamente do assunto, falando dos diversos conflitos e achei que valia a pena enumerar algumas das explicações que achei mais relevantes para discussão. Algumas das explicações auxiliam até a entender melhor outros conflitos.

1. O argumento mais óbvio é o treinamento das tropas. Alguns dos pontos dele são relevantes para outros argumentos. Como a maioria dos países árabes são monarquias e/ou ditaduras, a maior parte das forças armadas recebe um treinamento voltado para lidar mais com problemas internos, manifestações, tentativas de golpe e revoluções, do que uma operação militar convencional. Alguns analistas argumentam que o treinamento não é só inapropriado, mas inadequado mesmo. Na Guerra do Yom Kipur os egípcios treinaram por anos para fazer a mesma coisa, e fizeram bem feito quando era exatamente como esperava, mas não conseguiram fazer mais nada direito quando saiu dos planos.

2. Outro problema relacionado é que pelo fato da maioria desses países serem monarquias e/ou ditaduras muitos oficiais são apenas indicados, não chegando à posição por competência. Adicionalmente, por medo de um golpe de estado vindo dos militares, muitas indicações são feitas para deliberadamente gerar algum atrito e evitar uma união que levaria a isso. Esse atrito acaba indo para o campo de batalha também e elimina qualquer iniciativa. Soldados e oficiais preferem falhar do que tomar decisões por conta própria. Qualquer assunto militar é considerado segredo e oficiais são transferidos de forma imprevisível antes de poder formar alianças. Essa característica também presente na URSS acabou reforçada pelo envolvimento com os soviéticos pela maioria dos países árabes.

3. Isso gera um outro problema pois leva o conflito de classes que existe na sociedade para o campo de batalha, gerando hostilidades entreos homens . Para os homens de nível social baixo que ingressam nas forças armadas buscando oportunidades de ascenção social, um oficial indicado ao cargo representa uma ofensa. Pelo outro lado, a mesma discriminação social que haveria na sociedade civil acaba havendo entre o oficial indicado e seus homens. Isso é comum no Egito, onde há muitos relatos de oficiais que, sem nenhum laço com seus homens, simplesmente os abandonam no campo de batalha. Liderança não é considerada uma disciplina a ser aprendida, mas apenas assume-se que um oficial vindo de uma classe social superior seja um líder nato. O conflito entre oficiais também é constante por razões semelhantes, existindo uma disputa, e não há o mesmo grau de confiança que existe entre militares ocidentais.

4. A consequência mais óbvia desses três argumentos é a pouca coesão dos árabes em pequenas formações, a incapacidade de permanecer juntos e continuar a combater como grupo no calor da batalha, algo essencial na guerra moderna. Esse é o principal argumento que eu conhecia, porque é geralmente usado pelos militares israelenses. Desde a Campanha do Sinai em 1956, ficou claro para os israelenses como as unidades árabes perdiam sua coesão e deixavam cada homem por si ao sofrer ataques precisos e inesperados, algo que até ajudou a moldar a doutrina militar israelense a combater dessa forma.

5. Como muitos oficiais acabam chegando ao cargo por indicação, sem competência para tal, mesmo que permaneçam com as tropas, uma liderança tática rápida e eficiente é crucial para a eficácia nas guerras modernas, exigindo uma descentralização do comando e sub-oficiais competentes que consigam se adaptar com iniciativa e rapidamente às situações e conduzir tudo com fluidez. Isso é evidente em particular na Guerra do Yom Kippur, em que devido à surpresa adicional vê-se que tanto os Egípcios quanto Sírios lutaram com eficácia enquanto seguiam os planos originais, mas o nível despencou depois do ponto em que a reação israelense começou a ganhar momento e as decisões tinham que ser mais rápidas.

6. Outro ponto é a ineficácia dos árabes em adquirir informações sobre o inimigo e repassá-las eficientemente através da cadeia de comando. Não raro, em várias guerras, informações são deliberadamente distorcidas ou fabricadas para exagerar sucessos e ocultar falhas, principalmente por medo de represálias. Isso foi muito comum na guerra Irã-Iraque e na Guerra dos Seis Dias, chegando até mesmo ao topo da hierarquia. Difícil saber até onde foi fanfarronice e até onde foi falha de inteligência, mas por exemplo, a Jordânia chegou a lançar ataques fadados ao fracasso porque Egito anunciava que seus aviões já estavam bombardeando Tel Aviv quando na verdade foram destruídos no chão.

7. Muitos dos países árabes tem um nível educacional muito abaixo daquele dos países que lhes fornecem equipamento militar, e hoje as guerras dependem muito mais do conhecimento e manuseio eficaz dos equipamentos. Operar um tanque ou avião da segunda guerra mundial parece brincadeira de criança perto de todos os equipamentos computadorizados dos tanques e aviões modernos. Um argumento usado para explicar a ineficácia dos árabes em conflitos que dispõe de grande superioridade tecnológica, é não conhecer e explorar toda a capacidade dos equipamentos que dispõe devido às deficiências educacionais e ao treinamento inadequado. O nível de segredo e a paranóia constante que impera sobre todos os assuntos militares também impede a descentralização de manutenção e reparos de equipamentos, algo essencial nas guerras modernas.

Todos esses fatores, e outros que não foram comentados, culminam em uma esfera de ineficácia em todos os aspectos, desde o alto comando até o último soldado. Governantes impedem interação e treinamentos conjuntos entre as forças por medo de golpes, comandantes tentam microgerenciar qualquer aspecto das suas forças com medo de delegar autoridade, oficiais vêem soldados com desprezo e não se importam com eles e vice-versa.

Essas técnicas podem funcionar para manter uma ditadura, mas não para enfrentar um inimigo externo ou para sustentar uma democracia, daí a dificuldade em implantá-la nesses lugares.