All should definitely be primaried, yes. Here's to hoping the Obama administration fuels some strong candidacies against these joke Senators.
That's probably not going to happen.
Schumer has a good chance of being the Democratic leader, so no one in the administration wants the bad blood that comes with backing a primary challenger.
The Iran deal isn't that popular with the population so primary challenges on this basis aren't going to be good for the party's national image.
If things go badly in Iran, it's also not in the party's interests to have made a purity test on these grounds.
I'd imagine there will be primary challenges, but it's more because of the Sanders model than anything else. If a socialist can lead in primary polls, there's an opening for people running as socialist Senators. His campaign apparatus could also result in many current staffers running for office later (See Ron Paul.)