Caspar W. Weinberger, Secretary of Defense under President Reagan, made headlines around the world with his views concerning when the US should—and should not—use military power. He spoke in the aftermath of the Oct. 23, 1983, suicide truck bombing that killed 241 American servicemen, most of them Marines, who were in Beirut, Lebanon, on an ill-defined peacekeeping mission. Weinberger urged caution in use of force and, in this notable speech, listed six tests that should govern sending troops into combat.
The Washington Post immediately labeled this statement “the Weinberger Doctrine” (later misidentified by many as “the Powell Doctrine” and attributed to Secretary of State Colin Powell). Weinberger’s view is considered the intellectual counterweight to the so-called “Limited Objectives” doctrine, which holds that the United States can and should conduct limited military operations for limited political goals. The issue flared in a different form in the debate over the size of the force deployed to Iraq.
Once it is clear our troops are required because our vital interests are at stake, then we must have the firm national resolve to commit every ounce of strength necessary to win the fight to achieve our objectives. ... Just as clearly, there are other situations where United States combat forces should not be used.
I believe the postwar period has taught us several lessons, and from them I have developed six major tests to be applied when we are weighing the use of US combat forces abroad. Let me now share them with you.
First, the United States should not commit forces to combat overseas unless the particular engagement or occasion is deemed vital to our national interest or that of our allies. That emphatically does not mean that we should declare beforehand, as we did with Korea in 1950, that a particular area is outside our strategic perimeter.
Second, if we decide it is necessary to put combat troops into a given situation, we should do so wholeheartedly, and with the clear intention of winning. If we are unwilling to commit the forces or resources necessary to achieve our objectives, we should not commit them at all. Of course if the particular situation requires only limited force to win our objectives, then we should not hesitate to commit forces sized accordingly. When Hitler broke treaties and remilitarized the Rhineland, small combat forces then could perhaps have prevented the holocaust of World War II.
Third, if we do decide to commit forces to combat overseas, we should have clearly defined political and military objectives. And we should know precisely how our forces can accomplish those clearly defined objectives. And we should have and send the forces needed to do just that. As Clausewitz wrote, “No one starts a war—or rather, no one in his senses ought to do so—without first being clear in his mind what he intends to achieve by that war and how he intends to conduct it.” War may be different today than in Clausewitz’s time, but the need for well-defined objectives and a consistent strategy is still essential. If we determine that a combat mission has become necessary for our vital national interests, then we must send forces capable to do the job—and not assign a combat mission to a force configured for peacekeeping.
Fourth, the relationship between our objectives and the forces we have committed—their size, composition, and disposition—must be continually reassessed and adjusted if necessary. Conditions and objectives invariably change during the course of a conflict. When they do change, then so must our combat requirements. We must continuously keep as a beacon light before us the basic questions: “Is this conflict in our national interest?” “Does our national interest require us to fight, to use force of arms?” If the answers are “yes,” then we must win. If the answers are “no,” then we should not be in combat.
Fifth, before the US commits combat forces abroad, there must be some reasonable assurance we will have the support of the American people and their elected representatives in Congress. This support cannot be achieved unless we are candid in making clear the threats we face; the support cannot be sustained without continuing and close consultation. We cannot fight a battle with the Congress at home while asking our troops to win a war overseas or, as in the case of Vietnam, in effect asking our troops not to win but just to be there.
Finally, the commitment of US forces to combat should be a last resort. ...
These tests I have just mentioned have been phrased negatively for a purpose; they are intended to sound a note of caution—caution that we must observe prior to committing forces to combat overseas. When we ask our military forces to risk their very lives in such situations, a note of caution is not only prudent, it is morally required.