Of course they are! Opposition to Israel is part and parcel of the package that al-Qaeda represents. And so it make sense that, as a high profile enemy of Israel, persons upset with Israel for a variety of legitimate or illegitimate reasons will be attracted to it.
I do think Ackerman is right that some Jews get nervous when this is expounded upon too vigorously, because it can lead to Michael Scheuer-esque positions basically advocating throwing Israel to the wolves to appease al-Qaeda. But there are separate issues.
Moreover, Ackerman is clearly right about this:
The answer for the U.S. is not to sever ties with Israel or turn hostile toward it. It’s to seek an end to the Israeli-Arab conflict and a stable Middle East. That will not stop Islamic extremism. Maybe I should say it again in capitol letters: A TWO-STATE SOLUTION WILL NOT STOP ISLAMIC EXTREMISM. Extremists are going to be extremists. They demagogue. They use pretexts. That’s what they do. You deal with that. The proper response is to reduce the circumstances under which their demagoguery resonates. And that’s why ending the Israeli occupation of the West Bank and midwifing a Palestinian state is so important. This is in our interests, it’s in Israel’s interests, it’s in the Palestinians interests, it’s in the Arab world’s interests, and it’s expressly against al-Qaeda’s interests. It’s in absolutely no way an “appeasement” of al-Qaeda unless you believe that Arabs and Muslims are naturally inclined to bandwagon with al-Qaeda. And that makes you a racist and safe to ignore.
Maybe not "safe to ignore", because such racism still has plenty of purchase in American life. But the general sentiments are right.