The comparison we're making is whether precision attacks, presumably on roughly building-sized targets, would be cheaper to do from long range via ICBMs (with conventional warheads), or via much cheaper but shorter-range missiles. My guess is that neither ICBMs nor shorter-range missiles could have accomplished what the U.S. military accomplished in Iraq. Presumably missiles alone were responsible for a small portion of that $54 billion.
If I can trust https://en.wikipedia.org/wiki/LGM-30_Minuteman a Minuteman III (which is the current ICBM design used by the US) will land within 800ft (240m) of its intended target 50% of the time. And outside that circle the other 50%.
In other words, you can't really target a "building-size" target with these (with maybe exceptions like the Pentagon).
For nuclear payloads, a few hundred meters of error is much less of an issue, of course.
