Intercepted them all.
What would it have accomplished?
Restored security if not deterrence, since obviously retaliatory ability is virtually meaningless.
Wasting interceptors on flying soon-to-be-submarines, is dumb. As far as restoring security goes, we still have it, and the bad guys now know they can't find out how well our stuff works by using a cheap fireworks display.
China was no doubt behind the launches, they were HOPING we would engage so they could learn how our defenses work. But if they want to know, they have to actually shoot at something. They blinked, not us.