It is absolutely possible to be against the actions of the Israeli government yet not be an antisemite. Except in that I can't say they're wrong for trying to eradicate Hamas, I despise the current bunch of bastards in power in Jerusalem, and I've long held the opinion that continuing to expand settlements in the West Bank into areas deeply intertwined with Palestinian towns and villages is not just morally wrong, but also counterproductive for Israel's long-term interests.

However, anyone who is unquestioningly against anything Israel does and wants to see it destroyed is indeed an antisemite, perhaps externally adorned with the clothes of the "merely antizionist."