In concert with Israel and Washington's Zionist and fundamentalist Christian lobbies, the Bushites say their "strategy" is to end Iran's nuclear threat.
-- from AntiWar.com via The Leiter Reports.
Given that the Leiter Reports have tried to (rightfully) support the idea that one can criticize Israel's policies without being anti-Semitic, posting an article that uses a quote like the above strikes me as seriously problematic.
While there are certainly some self-identified Zionist organizations, and I imagine a few of which are worthy of criticism, the use of Zionist as a pejorative must certainly be understood to evoke emotional responses above and beyond what would be associated with the more neutral use of the term.
For instance, the above quote relies on the rhetorical image of the militant Zionist lobbying America to support their program -- an image evocative of the Protocols of Zion (an "antisemitic literary forgery that purports to describe a Jewish plot to achieve world domination"). If the writers did not wish to subtly or not so subtly conjure up these images, why use the term "Zionist" instead of the more neutral and less historically-laden term, pro-Israel lobby?
How many millions of people in the world when they hear "Zionist" think of the various competing political and ideological movements compared to how many think of the secret Jew seeking dominion over the world?
When I was in the service, some otherwise progressive folks referred to one of the black guys in our unit as a nigger. They quickly explained that here they meant simply "nigger as generic term for asshole", and that white guys could be niggers too. Admittedly, the guy was kind of an asshole. But we already have a more neutral and less historically-laden term for asshole.
It's called "asshole".