It's mostly cold war propaganda, because the USSR was pouring an incredible amount of it's economic output into defense spending since WW2. The star wars gap w

It's mostly cold war propaganda, because the USSR was pouring an incredible amount of it's economic output into defense spending since WW2. The star wars gap would have just meant that it couldn't maintain parity with the US on yet another battlefront, but nothing external was going to stop it from continuing on it's course. It would have had to reign in it's imperial ambitions some, but that is completely survivable for an industrialized nation. What killed the USSR was Gorbachev prioritizing butter over guns, and having a shred of humanity in him, by choosing to not respond to political problems with violence. He was the real hero of the crisis, not for the things he did, but for the things he didn't do.