If soviet union would have done that to west Germany, they would have had full load of US made ICBM's raining on Moscow about one hour after first detonation.

If soviet union would have done that to west Germany, they would have had full load of US made ICBM's raining on Moscow about one hour after first detonation. Nuclear weapons (like almost all military weapons) are about A. threatening B. revenging. These are commonly called first strike and second strike. U.S. currently builds B21 stealth bombers that can carry nuclear weapons, because the B2 has proved to be useful type of threatening tool. Such planes fly undetected in various airspaces and drop conventional bombs to countries who don't have nukes. The message is "we could nuke you and you would not know until it hit you, keep in line peasants". If you didn't want to send that message, you could use either non-nuclear rated stealth bomber or you could use non-stealth bomber. The second strike is hardened ICBM's in hardened bunkers. Idea is that when the infrared signature of enemy ICBM booster-phase is detected, you have about one hour time to pray and have sex and whatnot. So you use that time to launch your own ICBM's to revenge the impending doom. Because each side knows this revenge is coming, you are not very likely to see nuclear exchange between ICBM sporting states. You are quite unlikely to see any kind of exchange to be accurate. In case you just spot detonation, you can assume that enemy bomber has gotten through, so you might just as well again launch your ICBM's. The suspects of a launch are usually well known because enriching arms grade nuclear matter is very hard to do undetected. So Wolkswagen is not suitable because the enemy does not have time to feel threatened. And if you start your wolkswagen engine when nukes are raining, you are already several days late from your revenge mission.