The debate over possible U.S. military action against Iraq raises the question of whether a nation has the right to attack another country in order to prevent future threats and attacks. The United States argues that it needs to oust Iraqi leader Saddam Hussein because he poses a grave threat to international security if he has or acquires nuclear, chemical, or biological weapons. The controversy is over an emerging doctrine--the right of preemptive action to guard national and international security.

The Bush Administration's case for attacking Iraq rests on the assumption that dealing with Saddam Hussein now could save many lives in the future. If the Iraqi leader has or develops weapons of mass destruction, he could use them against his enemies, such as Britain and the United States, or transfer these weapons to terrorist groups such as al-Qaida. Saddam Hussein has already used chemical weapons against Iraqi Kurds and Iranian troops during the Iran-Iraq war of the 1980's.

In his speech last week to the U.N. General Assembly, President Bush outlined the reasons why he thought military action against Iraq may be necessary.

"We know that Saddam Hussein pursued weapons of mass murder even when inspectors were in his country," he said. "Are we to assume that he stopped when they left? The history, the logic, and the facts lead to one conclusion: Saddam Hussein's regime is a grave and gathering danger. To suggest otherwise is to hope against the evidence. To assume this regime's good faith is to bet the lives of millions and the peace of the world in a reckless gamble. And this is a risk we must not take.

The President called for the U.N. Security Council to enforce its resolutions on Iraqi disarmament, but he warned that a regime that has lost its legitimacy will also lose its power.

Former Secretary of State Henry Kissinger agrees with the principle of pre-emptive action in the case of Iraq, although he wants the Bush Administration to first focus on trying to get United Nations weapons inspectors back into Iraq.

Mr. Kissinger told NBC television recently that the threat from weapons of mass destruction in the hands of a leader such as Saddam Hussein underscores the need for possible pre-emptive action.

"The international environment has changed fundamentally from the period of the nation state and from a level of technology in which attacks could take place only from a nation state and in which technology did not permit a decisive early victory," he said. "We are now in a period where many of the threats are transnational, and where the threat of a first strike could be so overwhelming to civil society."

Mr. Kissinger said the purpose of military action against Iraq, if U.N. weapons inspectors are not allowed in, would be the removal of weapons of mass destruction. The former Secretary of State said a transparent system would then have to be put in place to prevent a similar occurrence in the future.

But some Democrats in Congress and foreign policy experts are skeptical about the need for a new doctrine of pre-emptive action, particularly against Iraq. Senate Democratic Majority leader Tom Daschle said last week that he believes the case for pre-emptive attack on Iraq has not been made conclusively.

Democratic Senator Bob Graham, Chairman of the Senate Intelligence Committee, argues the United States should rely on a strategy of deterrence. Mr. Graham told Fox Television Sunday that the Bush Administration should make clear that an attack on the United States or its allies by Iraq with weapons of mass destruction would bring a catastrophic response.

"I think it is very important that we be clear as to what our response will be not only with Iraq but with other nations that potentially have weapons of mass destruction to threaten their neighbors or the United States, and that reaction will be catastrophic," he said. "That is the strategy which for 40-years kept the Cold War in balance, and I think it continues to be an important principle of relations towards these rogue nations."

The concerns of Democrats in Congress will take on added significance if and when President Bush seeks congressional authorization for a pre-emptive strike on Iraq.