A deterrent is a means of getting the other side not to nuke you in the first place. If an attack occurs, that means your deterrent has failed.
A defense system is a means of intercepting nukes once the attack has started. I don’t think any country on the planet can do that reliably. And the reliability has to be extremely high to be worth anything at all, because even one nuke getting through can mean an entire metro area is leveled.
A deterrent is a means of getting the other side not to nuke you in the first place. If an attack occurs, that means your deterrent has failed.
A defense system is a means of intercepting nukes once the attack has started. I don’t think any country on the planet can do that reliably. And the reliability has to be extremely high to be worth anything at all, because even one nuke getting through can mean an entire metro area is leveled.