>is there any reason that isn’t an excellent idea?
yes. Missile shields threaten the ability of an enemy to retaliate, they're first strike enablers (so despite the name, effectively offensive weapons). The only rational choice for an opponent would then be to strike immediately before they're rendered defenseless. You would have effectively bought yourself an immediate nuclear war once Russia perceived that threat to be imminent.
Your existence hinging on a dictators mood isn't nice, but what's worse is making it game theoretically necessary for them to glass you immediately.
yes. Missile shields threaten the ability of an enemy to retaliate, they're first strike enablers (so despite the name, effectively offensive weapons). The only rational choice for an opponent would then be to strike immediately before they're rendered defenseless. You would have effectively bought yourself an immediate nuclear war once Russia perceived that threat to be imminent.
Your existence hinging on a dictators mood isn't nice, but what's worse is making it game theoretically necessary for them to glass you immediately.