[Aunche]

Iron dome can't even intercept all of the subsonic rockets fired by terrorists with very limited budgets. Even if the entire US GDP was directed towards missile defense, I doubt that China or Russia would have any trouble overwhelming these systems simply by throwing enough conventional MIRVs at it.

[towaway15463]

Being able to ensure a strike with a single missile is a force multiplier especially when it comes to deterrence. If you need 10 missiles to ensure one hit your enemy may think they have favourable odds in a first strike. If you only need 1 missile per hit then the outcome of a first strike is not so good if they don’t get every single one of your missiles.