A fortnight after taking office, the Reagan administration has taken shape. As expected, the president has proved to be a delegator -- a leader who reigns more than he rules.

His senior adviser, a man already being called the "prime minister," is his White House counselor, Edwin Meese. In addition, Secretary of State Alexander Haig is clearly asserting himself as the foremost figure in foreign policy -- to the point where he is being jokingly known as CINC-WORLD, which in military lingo means "commander in chief of the world."

The president's own role emerges from the numerous public appearances he has already made. So far they have been heavily ceremonial -- the inaugural address and the accompanying festivities; the welcome of the former hostages; five Cabinet meetings; and the signing of various executive orders purportedly cutting back government and regulations.

President Reagan's first press conference underlined further the honorific character of his leadership. It was a dignified affair, marked by a procedure for recognizing reporters as they sat, which avoided the mad scramble of rising and shouting for the president's attention. Apart from the formal announcements that he was cutting back the Wage and Price Council and putting a moratorium on new regulations, Reagan made no news. He postponed for the future almost all issues. Several times he said a matter hadn't come to him because it hadn't reached the Cabinet level.

His comments about the Soviet Union showed a disposition to repeat bromides that were somewhat out of date. His remark that Russia sought to achieve a "world socialist state" ignores 50 years of history. His assertion that the United States would like an arms control agreement with deep cuts, while faithful to campaign rhetoric, runs against American interests, and would almost certainly not be acceptable to either the Pentagon or Congress.

"Prime Minister Meese" accompanies the president to almost all business meetings. While perfectly polite, he does not hesitate to direct the boss. "That worked in California, but not here," he has been heard to say.

A network of former associates -- what one Republican senator calls the "Meese Mafia" -- has been established throughout the administration. The attorney general, William French Smith, the secretary of defense, Caspar Weinberger, and the secretary of health and humann services, Richard Schweiker, are, of course, well known to both Reagan and Meese through past associations. But as the deputies in departments headed by non-Reaganites, Meese has planted his own people. The list includes William Clark at the State Department, R. T. McNamar at Treasury, Richard Lyng at Agriculture and Darrell Trent at Transportation.

The Meese mode of operation seems to feature balancing tensions. Thus he is said to hold the ring evenly between the budget director, David Stockman, who is a crusader for tax cuts, and Treasury Secretary Donald Regan, who insists on pairing lower spending with lower revenue. Similarly, he has been balancing between Stockman and Energy Secretary James Edwards on deregulation of oil and between Stockman and Secretary Haig on foreign aid.

As for Secretary Haig, he has publicly asserted his primacy in the making of foreign policy on several occasions. His cheif appointments at the State Department are officials personally close to him with previous experience at the White House and the Pentagon as well as at State. He is evidently moving to constitute in the State Department a group that would replace the staff of the National Security Council as it existed under Zbigniew Brzezinski and Henry Kissinger.

The formal claim to that change is a memorandum submitted by Haig to the White House. It would transfer to State Department officials the leadership of all the top committees -- including those dealing with daily operations and foreign economic policy -- which used to be headed by White House officials.

That proposal, which has met resistance from the White House Chief of Staff James Baker and Meese, inspired the CINC-WORLD joke. Negotiations among Haig, Weinberger and Richard Allen, who heads the national security staff at the White House, are under way. The key issue is whether crisis management goes to State or the National Security Council. While not yet settled, it is hard to see how Allen can win. The fact is that he does not have a staff skilled in coordination. Haig does.

Between the establishment of machinery and the formulation of policy, to be sure, there yawns a wide gap. The Reagan administration has not yet begun to show that it can master inflation or contain the Russians. But if it makes the right decisions, it has the organization to carry them out and to save, in the bargin, the prestige of the presidency.