An interesting read:

When it Comes to Missiles, Don’t Copy Russia and China — Leapfrog Them

The idea put forth is to build booster rockets akin to but somewhat smaller than the Falcon 9, optimized to launch, land, refurb, reload and relaunch quickly. Put an upper stage on them (called a “bus” in the article, for reasons clear to anyone who knows anything about ICBMs), and then load the bus with weapons. The author suggest scramjet-powered cruise missiles. When the Chinese start lobbing intermediate range ballistic missiles at American and allied targets around the western Pacific, start lobbing weapons at *them* not from ships at sea, but form bases in the United States. The boosters get the bus to hypersonic speeds… and then they return for reloading and relaunch.

Done correctly, the expense should be that of the weapons themselves, the bus, and the propellant for the booster. Thus the weapons lobbed all the way across the Pacific *should* be cheaper than the weapons lobbed just from China to, say, Guam. The United States should be able to rain down a seemingly unending hail of weapons onto Chinese military targets.