A SMALL dispute that needs to be resolved quickly has broken out not over the United Nations Security Council's embargo of Iraq but over the manner of enforcing it. The United States, Britain and some other governments that have sent ships to the Gulf invoke the article (51) of the U.N. Charter that permits states to decide on their own how to apply force in aid of a member state under attack. But other countries, the Soviet Union and France among them, defer to another Charter article (42) putting it to the Security Council to determine how force is to be applied. In legal terms there is sturdy support for the American reading. But as Joseph Sisco argues on the opposite page today, for political considerations it needs to be reviewed.

Certainly the American government is not remiss in wanting to make sure the embargo is enforced effectively. President Bush made this plain yesterday when he suggested that interdiction of Iraqi cargo might yet be extended from the Persian Gulf and Mediterranean to Jordan's Red Sea port of Aqaba. A gap between word and deed has been a distinguishing mark of the United Nations. A case can be made that expeditiously tightening economic pressure on Iraq is essential both to avoiding further military action and to ensuring that the initial, broad resistance to the Iraqi invasion does not fade into the U.N.'s familiar dithering.

In this instance, nonetheless, there is reason for going through the Security Council to enforcement rather than having each nation act on its own. The basic embargo has already been voted, unanimously. Security Council enforcement may be slower, but it is almost certainly surer. It provides not just useful company and a lower profile for the United States but essential cover for foreign governments that may otherwise hesitate to stand up with Washington or to Baghdad. Merging the American intervention into a broader operation reflects the reality of the international scope of this crisis.

Pressed yesterday, President Bush allowed as how a joint United Nations command or an international fleet under the U.N. flag -- two devices that could be used in a blockade under Security Council auspices -- might be acceptable to the United States, though they were not, he said, essential. He pronounced himself ''somewhat open-minded.'' Fair enough. What is being proposed, after all, is unprecedented in postwar practice. It is well that the United States is part of the quest for answers to the difficult political and practical problems involved in making the idea work.