Terrorist was left loose to give cause for war.

Your recent article about the strange dealings of our government with a top al-Qaeda operative, Ali Mohamed, may be better understood in a historical light of the casus belli.

The Latin term, meaning a cause (or excuse) for war, has been employed to describe the machinations of kings itching to invade neighboring countries. One of the best known examples is the way that Otto yon Bismarck, the "Iron Chancellor" of Prussia, provoked Louis-Napoleon, Emperor of France, to declare war on Prussia in 1870 and then immediately attack France with great success, which led to the annexation of Alsace-Lorraine and the founding of the German Empire. Of course, this also led to the First World War and the destruction of the empire, perhaps a lesson for us.

Likewise, the U.S. government seized upon the sinking of the battleship Maine, an act of unknown parties, to declare war on Spain, though Spain had offered reparations. The pretense was the liberation of Cuba. The real objective was the conquest of the Philippine Islands. It took us two years and 66,000 dead Filipinos to complete their so-called liberation.

The sinking of the British liner Lusitania in 1915 was probably planned and calculated by then-First Lord of the Admiralty Winston Churchill. It carried 500 civilian passengers, many of them American, and was sent without escort into the path of German submarines. That event materially assisted in preparing the American public for war.

In 1941, President Roosevelt wanted war but the American public did not. He ordered the Japanese to get out of China, or America would cut off their oil supplies from the Dutch East Indies (now Indonesia). This was probably a bluff, but it worked. The predictable result was the Japanese attack on Pearl Harbor. Whether Roosevelt knew in advance of the day and hour of the attack is immaterial.

Fast forward to the 1980s. The United States builds a large air base in Saudi Arabia. Why? The answer came in 1991, when our ambassador to Kuwait, April Glaspie, virtually gave Saddam Hussein the green light for his invasion of Kuwait. This led to the First Gulf War, after which Bush the elder was prudent enough not to invade Iraq. Perhaps he thought that Saddam Hussein would learn a lesson and deal with the American and British oil companies. Had Hussein done so, he might be alive and well today.

Something like 9/11 was needed by the U.S. government as an excuse for an open-ended "war on terror." Whether they knew in advance of the exact day and targets is of no consequence. It was completely predictable and provided the excuse for an attack on Iraq on the pretext that Saddam Hussein was behind al-Qaeda--though al-Qaeda was actually Hussein's enemy. To make the invasion seem necessary, the Bush and Blair governments invented another casus belli, the Weapons of Mass Destruction, which of course did not exist. So they changed the name of the invasion to "Operation Iraqi Freedom."

Why are Iraqis so ungrateful? Alan Greenspan said it recently with unusual candor. The war was all about oil. And so is the War on Terror.

JUAN J. RYAN

New Providence, New Jersey