A fight over what counts as anti-Semitism has turned into an argument about how much sway Israel really has over US policy — bad for Shapiro, who critics say undercut his own case.

• Shapiro defined anti-Semitism as a conspiracy theory about Jewish power, not simple bigotry, and said claims that Israel runs US foreign policy fall into that category.
• To prove the point, he argued that if Israel truly controlled Washington there would be 200,000 American troops in Tehran right now.
• Critics seized on that line: if true, it means Israel would push the US into a war almost no American wants.
• They also flagged his remark that debate over Gaza would not exist if Israel ran things — asking what would silence that debate.
• Both sides agreed the "Israel runs America" phrasing is overstated, but split on whether the real influence is still too large.

Outlook: Expect the exchange to keep fueling the wider fight on the right over Israel policy and where criticism crosses into bigotry.