Allying With Stalin

Matt Glassman has a nice reply tweet this morning apropos calls for political purity: we allied with Stalin to defeat Hitler.

To me it's a two-fold reminder: 

• there's no purity in human beings, we're all a mixture of qualities. Stalin was an evil man but effective enough as a wartime leader. 
• our decisions are made in time.  As Churchill said; I'd ally with the devil to defeat Hitler.