Prevention of domestic crime and violent projection of power in international affairs are unrelated uses of the sovereign monopoly on force.

It is reasonable to object to USA's use of the latter while enjoying the benefits of the former. Indeed I do so.

It very well might. If I simply don't have enough shards of the key or keys for the multisignature address, sure, you can still kill me, but you can't get the money from me. It's impossible.

You can see my related comment below, but if you're motivated by the money, this protects me. You'll never get it if I'm dead.

If you're motivated by violence, though, nothing protects me. But the same is every bit as true if my money is in USD.