Again the last Russian icbm was built before the Soviet Union collapsed…I think with ICBMs the issue is they can be shot down, but if a full blown nuclear exchange there likely wouldn't be enough capacity to intercept whatever % of the russian ones made it out of Russian airspace and didn't simply fail completely, or in fact headed off completely to the wrong place (due to failure of varying degrees)
You would also need to hit them in the ICBM stage and not the final stage (the nuclear warhead stage) which would be incredibly difficult.
The amount of money the USA spends on maintaining their smaller fleet of nuclear weapons is larger than the entire Russian military budget, then when you take into account the rampant corruption. Those ibcms are more likely to be duds if not more harmful to Russia.
The USA has spent billions developing stealth bombers, you think the Russians would even get the chance to launch them?