AYATOLLAH KHOMEINI said Tuesday, in the speech excerpted on the opposite page, that President Carter "does not have the guts to engage in a military operation." The taunt is not entirely unfounded. Mr. Carter has regularly boasted that no American soldier has died in combat in his presidency. His diplomacy, in general, has relied on a premise of the other person's reasonableness that, to put it mildly, has not always been in evidence. Two weeks passed while Americans were held in Tehran, and Mr. Carter did not announce any readiness to use force in their behalf. For this he has risked giving the ayatollah the impression that he is a pushover. He has also paid a political price.

Now, by a careful message and by deploying the fleet, Mr. Carter has unsheathed the sword. It is, we think, the right move. If he -- we are tempted to say, even he -- has now decided to signal that the United States is prepared to use its power, then a long step forward has been taken in the Carter presidency and in the Iranian crisis, too.

Whether Ayatollah Khomeini can be reached by this demonstration, any more than he has been reached by appeals to his international obligations or by economic pressure and diplomatic isolation, cannot be foretold. Regardless, Mr. Carter had to put himself in a better position to move if the risk to the remaining hostages escalates further. And that risk may escalate -- by the ayatollah's threat to try the diplomats as spies, or by an Iranian reaction to a decision by the shah to return to Mexico, if that happens, or whatever.

The ayatollah might consider that through all of this period, the mood of the American people as a whole has clearly been hotter than Mr. Carter's. Our guess is that if the ayatollah forces him to act, Mr. Carter will have the near-unanimous support of the American people -- including, by the way, the support of those blacks whom the ayatollah seems to believe he weaned away by his selective release of hostages.

In fact, the indirect bargaining that has been going on for hostages has not ended. It has intensified. To mr. Carter's new show of military force, the ayatollah has responded with another by-now-familiar parade. The hostages are in danger. Yet events elsewhere in the Islamic world are running against the ayatollah. The economic pressures applied by Washington have been accepted as legitimate by almost every other Moslem state. The strange uproar in Mecca is bound to confirm the already-strong view in Islam's Sunni and conservative quarters that the ayatollah's revolution is a loose cannon of looming menace to them. The frightful mob attack on the American Embassy in the capital of Pakistan at least demonstrated that other Moslem governments, including one under great internal stress, accept their responsibility for the well-being of foreign diplomats. It remains for the ayatollah to accept that responsiblity too.