<p>Since the days of the Eighth Air Force in Europe, the strategic bomber has been the king of the US Air Force fleet. Vast armadas of large aircraft have been maintained to crush major enemies in all-out nuclear war. Their very existence can be seen as the primary defense against any such conflict, for any aggression against the United States would prompt the infliction of total destruction upon one's own nation. Today the current incarnation of that force still has a part to play, but the idea of a nuclear deterrent is seen by many as obsolete in the current political climate.
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<p>Three basic roles are flown by the strategic bomber force: penetration, stand-off missile launch and conventional tasks. The nuclear penetration role is the most dangerous, and calls for the most sophisticated aircraft — today, that role is entrusted to the Rockwell B-1B. Optimized for low-level attack, the B-1B carries a load of free-fall bombs and short-range missiles to attack key targets that may be well hidden or mobile. More obvious and fixed targets are earmarked for attack by air-launched cruise missiles, as carried by the Boeing B-52H. These are launched from considerable stand-off distances, thereby releasing the elderly Boeing bombers from the suicidal task of penetrating sophisticated defense networks. Some B-52s are assigned to the conventional bombing role, the 1991 Gulf War proving that the old dinosaurs could still play an important role in a conventional war if the air defenses could be sufficiently weakened to allow direct overflights of the target by these highly vulnerable platforms.
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<p>Entering service is the Northrop B-2, its stealthy planform allowing it to penetrate air defenses with far greater ability than the B-1B currently assigned to the role. However, the B-2 is the most expensive aircraft ever built, and it seems highly likely that only 20 will ever serve with the US Air Force, if the program survives at all. When the B-2A is in full service, some B-1Bs will assume cruise missile-carrying tasks. Highlighting the new-found flexibility of US airpower, both B-1Bs and B-2s have demonstrated awesome conventional bombing capabilities themselves, which are forming an increasing part of their repertoire. From 1996 the B-2 will be equipped with the 2,000-lb GPS-Aided Munition, to give a precision attack capability.
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<p>Strategic nuclear bombers at present only constitute one-third of the US deterrent 'triad', the other two-thirds being the submarine-launched ballistic missiles of the US Navy, and the nuclear missiles operated by the Air Force. The latter were the hardest-hit by the INF Treaty, the USAF having to destroy all of its ground-launched cruise missiles. This leaves it with a still-sizeable but slowly-reducing ICBM force consisting of silo-launched Minuteman and Peacekeeper missiles, but these are prime candidates for being bargained away in superpower arms restriction talks. As with the bombers, the missiles are expensive to acquire and maintain, and new procurement in the current world political climate seems highly unlikely.
