America's attention these days is properly focused on President Bush, who is making enough tough decisions to justify his salary and then some. Tough as these presidential decisions have been, however, the American public doesn't get to know much about how they are reached.

What we don't know, in any detail, is how broad a spectrum of advice Bush is receiving, whether on the gulf war, the Soviet Union's turmoil or any other pressing issue. Has he, before making a critical decision, sought out contrarian viewpoints and weighed conflicting evidence? Or has he relied on a cluster of like-minded advisers to deliver recommendations by consensus?Such questions cannot be answered with certainty yet, because we don't have more than an occasional glimpse at the inner workings of the Bush White House. But it would not be surprising if, years hence, memoirs were to recall that the advisers closest to Bush felt quite alike on critical issues, especially those involving national security.

Secretary of State James Baker, after all, has been a close Bush friend and confidant for many years. Deputy Secretary of State Lawrence Eagleburger was a protege of Henry Kissinger, as was former Gen. Brent Scowcroft, the president's national security adviser. Gen. Colin Powell, chairman of the Joint Chiefs of Staff, is himself a former national security adviser.

Patently, these men all excel at what they do, and all share the president's esteem. Why? At least in part, I'd suggest, because they share some basic perceptions and tend to see the world from similar perspectives.

Why not, indeed? Presidents, like most executives, tend to rely on advice from known associates whose judgments they can rely on. This tends to mean that they surround themselves with people of familiar views and familiar instincts. And this can mean, when decision time comes around, that offsetting arguments don't get easily heard.

Bush is hardly alone among presidents in wanting to surround himself with aides who share his basic outlook. Every president of the past generation, in fact, has had an inner circle of advisers who could be counted upon, most of the time, to deliver advice that would go down well in the Oval Office. The secretive Richard Nixon had his secretive Californians, John Ehrlichman and Bob Haldeman. Gerald Ford had the dutiful Don Rumsfeld and his deputy, Dick Cheney, now secretary of defense. Jimmy Carter brought up a tribe of loyalists from Georgia, some of whom found Washington beyond their capacities. Ronald Reagan had, I suppose, Nancy and her astrologer.

But a president, of all people, badly needs to have someone around who can be counted upon to ask awkward questions and challenge prevailing assumptions. A president needs a devil's advocate, some thick-skinned and independent-minded soul who, even in a crisis, can look at the decision memos and option papers and find flaws in the majority argument.

Such a position should be made a permanent part of the presidential team. The job might be titled something like "Special Assistant for Saying No." It would be a demanding job, because the occupant would get yelled at a lot for peddling unpopular views; and since people hearing bad news are prone to dispatch the messenger, his on-the-job tenure might be pretty short. Any such official, to succeed, would have to have the stomach to flag impending decisions that he saw as dead wrong.

Nonetheless, a devil's advocate on any president's staff, being paid specifically to ferret out the nasty what-if? questions and see that his boss squarely faced them, could perform an invaluable service. By waving the caution flag before a crucial presidential directive were signed, an Assistant for No could give an administration valuable time to reflect. And - who knows? - such a pause might help steer future presidents away from some decisions they otherwise would come to regret.