I had a professor who would shout “Anti-Semite!” at the elevator if the doors closed before he got on. This was at our rabbinic school, no less. His purpose was to remind us that not everything that happens is because we’re Jewish; some things just happen.
Because of that lesson, I’ve always been very cautious about charging someone with anti-Semitism. Sometimes people just have different ideas than I do, or than Jews do, and we have to respect those differences of opinion. But I believe the current BDS Movement (Boycott, Divest, and Sanction) against Israel has genuine anti-Jewish sentiment at its foundation.