All Russian boomers with SLBMs were all tailed by US attack subs. Our subs were very good at finding and following them after they left Russian ports and went to open waters. If a Russian boomer got off missile shots depending where they were in open waters, it would be about 10 to 15 minutes before they would strike their US targets. The warning would go up to about 30 minutes warning time for Russian ICBMs before striking the US. A good portion of our standby bomber force if not all would be in the air within 30 minutes. The Russian SLBMs at the time were not all that accurate and would be targeting softer targets like US bomber bases instead of hardened Minuteman II, III, and Titan ICBM silos. Our ICBMs would have enough time to launch on warning before they would get hit before a half hour expired. And moreover, about 25% of our nuclear SLBM submarine force would be out to sea at any given time of the year and they would have rained destruction on the enemy.
Contrary to the conclusion of this documentary, our nuclear forces would have been more than sufficient to hammer the Soviet Union in retaliation. BTW, I remember this film when it was first broadcasted.
saved for later
It wasn't effective, but it didn't matter as eventually the Peanut Farmer was ejected and Mr. Reagan took care of it from there.