But in an aggressive assertion of Congress's role in foreign policy, the new Republican Speaker, J. Dennis Hastert, refused to delay the debate.

''I have tried to be direct and honest with the President and his Secretary of State,'' Mr. Hastert, of Illinois, said in a speech on the House floor. ''I told them that I believed it was my duty as Speaker to insure that members of the House of Representatives, Republican and Democrat, have the opportunity to fairly and openly debate this important issue before troops are sent into a potentially dangerous situation.''

The day was a test of how Mr. Hastert would compare with Newt Gingrich, who was a confirmed internationalist. Although he refused to tip his hand in advance and did not vote on the Fowler amendment, in the end he supported Mr. Clinton.

''Any time we send our sons and daughters into harm's way, it is a tough decision,'' he said in a statement after the vote. ''But I do believe America has a vested interest in supporting NATO and in keeping peace in Kosovo.''

His stand put him at odds with the two senior members of his team.

The House majority leader, Dick Armey, and the Republican whip, Tom DeLay, opposed deploying troops. Mr. DeLay called the plan a ''big dangerous quagmire'' and ''another bad idea in a foreign policy with no focus.''

He said the Clinton Administration had become too dependent on air strikes and the threats of air strikes, referring to bombings in Iraq, strikes against targets in Sudan and Afghanistan and the threat of strikes in Serbia.

''Bombing sovereign nations for ill-defined reasons with vague objectives undermines American stature in the world,'' Mr. DeLay said. ''The international respect and trust for America is diminished every time we casually let the bombs fly. We must stop giving the appearance that our foreign policy is formulated by the Unabomber.''