Except when they were invading Poland in a relationship, Stalin was shocked to find out that Hitler turned on him.
“Stalin was shocked to find out that Hitler turned on him.”
Putin will probably be shocked when the Chinese communists turn on him.
There is no honor among thieves.
Poland wasn’t the only part of that deal; while Germany took Western Europe, Stalin was allowed to take Eastern Europe (part of Finland, along with the entire countries of Estonia, Latvia, and Lithuania).