No one is saying it isn't against federal law.

It's still a demented justification to turn someone away from the country. "You can come here, buy weed in a majority of states, and face no fear of repercussions... Until you try and come back in". That's nutty. It's batshit.

And, the real reason he was brought in - as brought up by the Immi officers - was that he was doing journalism at one of the anti-genocide protests.

It's probably not a good idea to have people on visas attending protests.

Keep in mind I'm very much not pro Isreal, but it's not practical or moral to have foreign partisans participating in our politics that way.

> > it's not practical or moral to have foreign partisans participating in our politics that way.

That would be called 'freedom of assembly', which is a universal human right (see Article 20 of the UNDHR). Highly moral, most practical, and widely recognized as such.

Why would someone on a visa deserve to be denied freedom of assembly?

Because that is the proven way to carry out regime change.

Sorry. No. The idea that you have a right of assembly in a foreign country is completely absurd. I don't know which line of thinking convinced you otherwise but any country that actually chooses to allow that can't exist for very long.