No one knows. This isn't the Cold War. Russia is so corrupt so who knows who much money they spent on updating their missiles. USA is a basketcase now, I assume our missiles are still in working order but how many of them are new? What is the failure rate for our aging missiles?
The problem is that missile technology has improved radically in recent years.
Old missiles are just not in the same league as new ones.
One commentator on the web recently said that a new missile was two orders of magnitude greater technology than a twenty year old missile in all respects—speed, guidance, “artificial intelligence”, etc.—and that offensive technology has rapidly outstripped defensive technology during the same period.
Westerners just do not talk about this stuff—they are in deep denial.
Did you forget? President Trump upgraded our entire military. He boasted about good it had become because of his efforts.