Text: They don't understand that the allies compromised with each other and with Russia because they sought long-term peace--not short-term gratification--and that such peace requires a level of deterrence that can be achieved only by an international consortium of civilian leaders.
Entailment: The allies made a compromise with each other and with Russia because they wanted long-term peace.
Contradiction: The allies didn't make a compromise with each other and with Russia because they wanted long-term war.