After years of glowing coverage and avid speculation about his political future, it's time for news media to start asking tough questions about Colin Powell.

Release of the retired general's autobiography is set to tip over a huge row of PR dominos this fall. And with a Time cover story featuring book excerpts and network TV interviews kicking off a whirlwind 25-city tour, Powell's media star is likely to rise into the political heavens.

Amid all the hoopla about the first black American to become a four-star Army general and chairman of the Joint Chiefs of Staff, the media spin presents Powell as a paragon of integrity and human values who could transform American politics in 1996.

Declaring that Powell ''could win the presidency,'' Time magazine asked: ''But is he bold enough to go for the top job and take on the political establishment?'' An odd question -- since Powell's career was made possible by the political establishment.

In fact, it's the establishment that would fund a Powell-for-president campaign. A ''former Pentagon official who now works in corporate America'' told Time: ''I could raise $ 50 million in one month just from the CEOs I know.''

News outlets have been slow to examine some aspects of Powell's record as a high-powered general. Here's a sampling:

As a top deputy of Secretary of Defense Caspar Weinberger, Powell oversaw the Army's transfer of 4,508 TOW missiles to the CIA in January 1986. About 2,000 of those missiles became part of the arms-for-hostages swap with Iran -- a transaction that Powell helped to hide from Congress and the public.

Soon after becoming President Ronald Reagan's national security adviser in 1987, Powell established himself as a point man for U.S. efforts to overthrow the government of Nicaragua.

Traveling to the region in January 1988, Powell threatened a cutoff of U.S. aid to any Central American nation balking at continued warfare by Contra guerrillas in Nicaragua. He pushed for U.S. financing of the Contras and worked to sabotage the peace process initiated by Costa Rica's president, Oscar Arias.

On December 20, 1989 -- three months after Powell became chairman of the Joint Chiefs of Staff -- the United States invaded Panama, killing hundreds of civilians in the first hours. That day, Powell proclaimed: ''We have to put a shingle outside our door saying, 'Superpower lives here.' '' The Organization of American States voted 20 to 1 to criticize the invasion. But Powell -- who saw it as a great way to guard against Pentagon budget cuts -- ''emerged as the crucial figure in the decision to invade'' Panama, reported Martin Walker, a British newspaper correspondent covering Washington. ''Among his military peers,'' the reporter noted, Powell ''may yet go down as the man who saved the Pentagon's budget.''

Six months after the bloodletting in Panama boosted the U.S. military's stock at home, Powell delivered a speech charging that if Congress cut the Bush administration's proposed military budget of $ 303 billion, it would ''force us to start breaking the back of our armed forces.''

In 1992, Gen. Powell took the extraordinary step of publishing articles -- promoting his own views of foreign policy and appropriate military intervention -- in the New York Times and the Foreign Affairs quarterly.

Later on in his stint as head of the Joint Chiefs of Staff, Powell moved closer to insubordination. Defying the commander-in-chief in early 1993, Powell went public with fervent opposition to ending discrimination against gays in the military. Powell spread the word that he'd resign if President Clinton didn't back down on the issue.

During the early 1990s, Powell became a military tail that often wagged the civilian dog.

A former chief historian of the U.S. Air Force, Richard H. Kohn, calls Powell ''the most powerful military leader since George C. Marshall'' and ''the most political since Douglas MacArthur.''

Writing in the conservative journal the National Interest last year, Kohn concluded: ''It was under Colin Powell's tenure that civilian control eroded most since the rise of the military establishment in the 1940s and 1950s.''

When we interviewed him a few days ago, Kohn was emphatic: ''The trend in the last 25 years has been a weakening of civilian control of the military, and we've seen it most glaringly in the last 10 years.''

As the nation's highest-ranking military officer, Colin Powell played a central role in undermining civilian authority over the armed forces. Now, as he considers a run for the White House, journalists have a responsibility to scrutinize his record.