Gulf attack mutes War Powers talk. Members of Congress, though in disagreement on American policy in the Gulf region, overwhelmingly supported Monday's attack on an Iranian oil facility.

The smoke from yesterday's American attack on an Iranian oil facility threatens to settle over Capitol Hill, further clouding Congress's continuing efforts to leave its stamp on United States policy in the Gulf region. For several months, lawmakers have struggled with each other and with the Reagan administration over strategy in that area. Some of the fiercest rhetoric has peppered the lengthy and inconclusive debate on whether or not to invoke the War Powers Resolution, which gives Congress the authority to call home troops deployed in an area of the world where hostilties seem imminent.

Now that US forces have actively been engaged in hostilties, lawmakers are groping for the next step. Many members of Congress are clearly nervous about the prospect of escalating hostilities involving American military personnel. At the same time, however, they do not want to be seen to be undercutting the US posture internationally.

No sooner had word of yesterday's attack reached Washington when congressional leaders from both parties expressed support for the action. ``There is no question the United States has to support its interests in the Gulf,'' stated Rep. Dante Fascell (D) of Florida, chairman of the House Foreign Affairs Committee. He called the US action ``carefully calculated'' and ``measured and restrained.''

A few senior lawmakers performed verbal contortions to avoid directly criticizing President Reagan or the action. House Speaker Jim Wright (D) of Texas, who last week strongly condemned the President's refusal to invoke the War Powers act, refused yesterday to repeat his complaints. ``I can't recall them,'' he jested. ``I'm not going to be anyone who presents to the world a demonstration of a country divided by political partisanship.''

But the war powers debate is far from over and far from quenched by the US action. A few opponents of invoking the act asserted that to do so now would send a signal of America irresolution to the Iranians and to the world. In a meeting with congressional leaders Sunday night, they point out, the President served notice of the impending action and promised to send Congress a full report within 48 hours of the strike.

``That puts him within the letter of the law, if not the spirit of the law,'' says House minority leader Robert Michel (R) of Illinois. But advocates of invoking the War Powers act say that is not enough. Yesterday's actions make invocation more critical than ever, they say.

``If anything, it may make the debate over war powers more intense,'' asserts House majority leader Tom Foley (D) of Washington.

The next round in the war powers debate was scheduled to take place today. The Senate was scheduled to vote on a compromise War Powers resolution endorsing the US presence in the Gulf while expressing ``reservations'' about the policy of reflaging Kuwaiti tankers and accompanying them with US Navy escorts. Observers close to the effort predicted that the resolution would be defeated because it fails to satisfy those calling for the invocation of the act itself even while it asserts too much congressional power for the taste of those who adamantly oppose the War Powers act.

Ultimately, says Mr. Fascell, Congress could settle on a general resolution supporting US policy in the Gulf, thus maintaining the appearance of congressional input into policymaking. But ``you can't really get that without getting cooperation from the President,'' he added. He did not specify what that cooperation would entail.