I hadn't heard this one.
In 1945, Churchill walked into the men's room at the House of Commons. Standing at the first urinal was Clement Atlee, the new Prime Minister. Churchill passed him and took up his position at the far urinal.
Atlee shouts down to Churchill, "Why so standoffish, Winston?"
Churchill, unbuttoning his fly, replied "Because, Clement, whenever you see something large you want to nationalize it!"