Appalled by Israel’s carpet bombing of Beirut during the 1982 Lebanon war, US President Ronald Reagan didn’t mince his words with then-Israeli Prime Minister Menahem Begin.

“I was angry. I told him it had to stop, or our entire future relationship was endangered. I used the word holocaust deliberately & said the symbol of his war was becoming a picture of a 7-month-old baby with its arms blown off,” Mr. Reagan noted in his diary.

The August 1982 phone call between Messrs. Reagan and Begin provides a template for the United States’ ability to twist Israel’s arm and the limits of America’s influence.