Basically, Sherri's idea had to do with bringing Fat's mind down from the cosmic and the abstract to the particular. She had hatched out the practical notion that nothing is more real than a large World War Two Soviet tank.
Liberals are constantly wrong. In fact, that's how you rise to the top in liberalism, by being wrong. If you are wrong, and if you are consistently wrong, it's even better. You're really one of them if you're really wrong all the time. Look at Jimmy Carter.