Kenan Malik, writing in the New York Times, makes some salient points regarding the left and anti-Semitism:

"Yet neither the cynicism nor the hypocrisy should distract us from the problem of anti-Semitism — not just in the Labour Party, but on the political left more generally. It is not that the left is packed with anti-Semites; rather, too many among them have been willing to accommodate bigotry.

This acquiescence is rooted in the changing character of the left in recent years. Anti-Semitism used to be a problem primarily of the right. It wasn't that the left had a totally clean bill of health — there is a history of left-wing anti-Semitism — but its firm foundation of universal values and egalitarian principles established a proud tradition of fighting bigotry against Jews.

In recent decades, however, much of the left has retreated from these commitments."

The British Left's 'Jewish Problem'