Opponents of the decision to remove Saddam Hussein like to argue that the war in Iraq is a diversion from the war against terrorism, since Iraq is a state, not a terrorist, and there was no connection established between Iraq and the terrorist attack on the U.S.
But this completely ignores reality. Terrorism can be defeated only by governments -- acting with the support of as large a share of their populations as possible. While part of the fight against terrorism is the pursuit of individual terrorists and terrorist organizations, the main requirement for defeating terrorism is to induce all governments to exclude terrorist organizations from their territory.
Therefore the test of whether removing Saddam was part of the war against terrorism is whether doing so helped or was necessary to induce Arab and other governments to stop harboring terrorist organizations.
But, opponents may ask, if one of the real reasons for removing Saddam Hussein was to convince Arab and other governments that they would have to stop harboring terrorist organizations, why didn't President Bush say so? Why did he never give this reason? The answer should be clear. One of the first rules for successfully intimidating a government is to deny that you are trying to do so. One does not make open threats. One acts in a way that leads other governments to understand the practical choice they face - as the government of Libya did when, following the attack on Saddam, it gave up its programs of WMD and of support for international terrorism.
The big hidden debate in Washington is about the choice of approaches to convincing Arab and other governments that they must refrain from harboring terrorists. The approach of the State Department, which has driven much of the administration's actual policy, is to appease these governments, assuring them that the US is sympathetic to their concerns and interests - such as "ending the conflict between Israel and the Palestinians," and trying to convince them of the advantages to them of acting against terrorism.
The alternative approach, which is recommended by some of the scholars with the deepest understanding of Muslim history and culture, is to compel the Arab governments to act against terrorism and stay away from WMD by making them afraid of what will happen to them if they fail to do so. The experts argue that the Arab governments cannot be led to want to take the necessary actions, and will take them only if they fear the consequences of failing to do so.
Of course in practice actual policy must be a subtle combination of the two approaches. The U.S. cannot act like a swaggering bully. But in the end we must choose which approach is the real basis of our policy - appeasement or intimidation; because the two approaches are fundamentally contradictory.
Saddam Hussein's Iraq was a dominant element in the Arab world, living and decisive proof that a government determined to defy the U.S. and the UN, and to harbor terrorists, could survive. No policy of compelling Arab and other governments to stop harboring terrorists had any chance of working while Saddam ruled Iraq. These governments would not even begin to take seriously American or other efforts to convince them to give up support for terrorism and WMD so long as Saddam Hussein continued in power.
While removing Saddam was never thought to be sufficient to defeat international terrorism, it was clearly a necessary first step. The idea of fighting terrorists without changing the policies of the Arab and other governments that harbor and support terrorism is not serious.