BEACH THE NAVY:

3. Cruise missiles, launched from sea, can do anything airplanes can do, but without endangering pilots.

Tomahawks are expensive -- between $1 million and $2 million each. Precision-guided bombs dropped from airplanes are cheap -- tens of thousands of dollars apiece. The United States may have several thousand Tomahawks in its arsenal; it probably has hundreds of thousands of gravity bombs. A gravity bomb can deliver at least twice as much high explosive as a cruise missile. Because of the physics of being dropped from a plane at 10,000 or 20,000 feet, a bomb with a hardened nose can penetrate layers of reinforced concrete. To take out an underground bunker (rather than, say, a radar site or another soft target), you usually need gravity bombs.

Moreover, it is relatively easy to turn airplanes around, up to the last moment. The crews of aircraft carriers welcome back the pilots of F-18 fighters; the crews of missile-firing destroyers do not welcome back Tomahawks that have decided to return to base.

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