President-elect George Bush's choice of Brent Scowcroft as national security adviser foretells a fresh review of U.S. aims in arms-control negotiations with Moscow and a skeptical new look at the goal of cutting strategic nuclear weapons by 50 percent.

The proposed halving of intercontinental weapons stockpiles reflects President Reagan's urge for deep nuclear cuts, Scowcroft has said. But there "has been no kind of process" demonstrating how the cuts would stabilize the military balance between the superpowers and better deter nuclear war, he has said."Why do we want to play with success?" Scowcroft has asked, referring to nuclear deterrence strategy of the past 40 years. "The arguments for deep cuts are unpersuasive, (although) I'm not saying they are wrong."

U.S. and Soviet delegates in Geneva have been trying for several years to negotiate an agreement that would cut each side's strategic arsenal to 6,000 nuclear warheads, a 50 percent reduction.

The return of Scowcroft to the White House - he was President Ford's security adviser - ensures a new assessment of how right or wrong the arguments are and how arms-control proposals in general fit into an updated strategic concept for U.S. defense.

Scowcroft, who will be Bush's most experienced hand in foreign and military affairs, is one of numerous authorities, including Ford's secretary of state, Henry A. Kissinger, who believe that a pause and new look at arms control aims are in order.

In the related area of the Strategic Defense Initiative, the retired Air Force general has been an agnostic. But he believes that some sort of ground-based version to protect missile and bomber bases may be feasible and necessary.

The presidential transition report handed Bush last week by former Presidents Carter and Ford warned about the heavy cost of a full-scale pursuit of SDI - popularly known as "Star Wars" - for continent-wide defense. The report's section on that and other security issues was written by Scowcroft and R. James Woolsey, Carter's Navy undersecretary.

Such an SDI commitment could turn into the new administration's "major governmental initiative" and, if it did, it could forestall "many other courses of action" in defense and elsewhere in government, the report said.

Scowcroft, a major, if quiet, voice on security matters for 20 years, takes singular advantages to the White House post.

They include long acquaintance with, and the confidence of, Bush, who directed central intelligence when Scowcroft served under Ford. He has a considerable leg up on James A. Baker III, the secretary of state-designate, in foreign affairs experience. He is widely respected for that on Capitol Hill.

Most important, as national security adviser he will sit in the White House and have constant access to the president.