Ron Brownstein: “President Donald Trump’s choice to launch a joint military campaign with Israel against Iran represents the crowning achievement of Israeli Prime Minister Benjamin Netanyahu’s decades-long campaign to court the Republican Party’s most conservative elements. But like the attack on Iran itself, that may prove a short-term success with heavy long-term costs.”“Over Netanyahu’s three decades at the center of Israeli politics, support for Israel has plummeted among rank-and-file Democrats in America, which has liberated a new generation of party leaders to forcefully criticize Israel. Now, the Iran war threatens to widen an incipient generational divide within the GOP.”