"I'm working harder but enjoying it more," Ed Muskie says of his new job as secretary of state. He generally rises at 5:30, reads cables and papers at home and reaches the office at 7 in the morning. He does not quit until at 12 hours later -- a far more rigorous schedule than in the Senate.

He still shows signs of being the new boy. He is not altogether sure which meeting is scheduled for Vienna and which for Venice. Nor is he totally at home with the various committees of the National Security Council system.

But he has developed a general foreign policy strategy -- a strategy for at least controlling the damage between now and the election. Basically what Muskie would like to do is to reestablish harmony between the United States and its principal allies on dealings with Russia, the Mideast and the Persian Gulf.

The new secretary does not expect uniformity or unity of views. But he would like the policies of the United States and its allies to work in complementary fashion rather than at cross-purposes.

He knows the Europeans have a special interest in detente with Russia, but he does not think that they have to pursue that interest in ways that undermine the efforts to make Moscow pay a price for the invasion of Afghanistan. He understands the Europeans and Japanese feel that sanctions against Iran are unproductive, but he claims they can behave in a way that does not vitiate American moves to apply pressure on behalf of the hostages.

He realizes the Europeans are pessimistic about chances for moving beyond the Egyptian-Israeli peace treaty to accord on Palestinian autonomy. But he believes they can launch a new initiative that promotes rather than destroys the joint efforts of Israel, Egypt and the United States to foster peace in the area.

Formidable obstacles stand in the way of realizing even those limited hopes.

The evidence suggests that the Europeans, especially the French, conceive of the new initiative in the Mideast as a means of profiling themselves against the United States as more favorable to the Arabs. In other words, they may not want a position that could be harmonized with the approach of Washington.

Consultation among the allies is inevitably tricky. Muskie feels he has established good personal relations with his main opposite numbers: Carrington of Britain, Francois Poncet of France and Genscher of West Germany. But the French will consult on political matters only within a four-power context. The Italians and others want in. If only because it takes place on Italian soil, the Venice summit on June 22 and 23 will not be propitious for detailed political talks.

More may emerge from the NATO foreign ministers meeting in Ankara a couple of days later. Muskie would eventually like to establish a new consultative mechanism -- but only in the future, if President Carter wins reelection.

The White House also presents some problems for Muskie. Not, as widely advertised, in the person of Zbigniew Brzezinski, the president's special assistant for national security affairs. Muskie is steadily cutting away at Brzezinski by assigning State Department people to jobs the NSC staff used to handle. "He plays Zbig like a yo-yo," one assistant secretary of state says.

The great problem for Muskie -- as it was for Cyrus Vance before him -- is Jimmy Carter, and his irrepressible habit of trying to make domestic political points by foreign policy actions. For example, Carter's statement that the United States would use the veto against any European initiative at the United Nations may win him some Jewish votes. But it weakens the chances of subjecting the Israelis to a little pressure for more concessions on Palestinian autonomy.

Still Muskie is plainly a far tougher customer for the White House than Vance. As a senator he was more used to shoving than being shoved. He has reinforced his political base by forging especially close ties to two senators in position to damage the president -- Minority Leader Howard Baker and a foremost Democratic apostle of stronger defense, Henry Jackson -- who were his luncheon guests on Friday. It is a mark of Muskie's independence that he agreed to go to a meeting of Southeast Asian countries in Malaysia at the end of this month, although Carter had personally asked him not to attend.

What remains in serious doubt is the shape of policy after the damage-control operation Muskie envisages for the next few months. So far he has shown no signs of changing either the course or the crew he inherited from Vance. But was the Vance policy such a raging success that it does not merit fundamental reexamination? Can those who conceived the policy comprehend its limitations? Can new measures be taken without new men?