Conventional wisdom might say that airbase hardening was demonstrated to be foolhardy in the 1991 Gulf War. USAF precision guided weapons demolished Saddam’s hardened aircraft shelters. But is it really still so foolhardy? Let’s set aside a convenient mountain to hide your planes under, and think about the traditional Hardened Aircraft Shelter: a small hangar covered with a good deal of reinforced concrete and other armoring materials.

Let’s also suppose, of course, that we’re in an operating environment where the question has some merit. That is, we’re in an area where there are reasonably proximate threats. The mental calculus is different in the middle of Nebraska or Siberia than for most parts of Western Europe. Fortunately, that is where Borgundy is.

We know that with sufficient application of firepower, any target can be destroyed. Emphasis on the word application–only hits count. This is where the precision comes in. Precision guidance kits have massively increased the hit probability. If we can see it, we can hit it. And if we can hit it, we can kill it. And aircraft shelters, hardened or not, are pretty easy to spot.

The Iraqi experience in 1991 bears this out. Shelters didn’t last. The Iraqis were unable (or unwilling) to contest the coalition airstrikes, so coalition airpower hit targets at will. Tougher shelters might have taken multiple hits, but precision guided munitions made this easy.

All of this is true. But note that the bombs used in Desert Storm were big. 2,000-5,000 lbs big. And the coalition air forces were able to operate with impunity. Suppose we have a more aggressive, competitive air force, and a more useful air defense system. In other words, suppose a peer opponent. Unless your ‘peer’ is the United States, your opponent will not have a near-limitless supply of precision guided munitions.

You will not be able to harden your shelters against everything, of course, but you can harden them against a strike or two from 1,000 lbs class penetrator warheads. Why 1,000 lbs? Because those bombs are easy to carry in quantity on tactical fighters, and that’s the size warhead you can fit on a Tomahawk cruise missile. And the Tomahawk is widely emulated. That’s a pretty standard size for a large cruise missile. Long range, 1,000 lbs warhead. Smaller cruise missiles have tend to have significantly shorter range and similar warhead sizes.

Cruise missiles are cheap, accurate, and effective. They’re hard to stop, being significantly smaller than a fighter aircraft and flying low and fast. And if they are downed by a high-end air defense system, there are now POWs or friendly casualties to see on the evening news.

So the goal is to remove some low-risk, low cost means of attacking your hard targets. Force them to increase missile count and bombs, meaning more sorties.

Now all I need is some cost estimates for a bunch of bunkers.