It takes time and it aint cheap.
“It takes time and it aint cheap.”
Yup. OTOH, a successful missile attack on, say, LA is quick and would be very expensive. As is blackmail thru the threat of a missile attack.
Missile defense, or lack thereof, will be (imho) the most important technological issue for our nation over the next fifty years. The offensive technology is getting too cheap and easy for folks who don’t care much whether they hit a target precisely. A nuclear weapon does not even have to hit the broad side of the barn to be an effective terror weapon.