Think again and it's the public school, free speech is for everyone not just the people you disagree with.
As long as she's not guilty of libel or slander, then it's free speech. That's always been my problem with people, they tend to stretch and, eventually, break the truth. They also tend to stalk and harass people, trying to get them to change their position.
If you tell a military recruiter "no," then they have to leave you alone. If they don't, then they are not allowed back on campus. If more than one recruiter causes such an issue, the entire branch could be disallowed on campus. As long as they apply that equally to all people, then I'd say we're fine. But when they let someone on-campus that guilts those who join, and harasses them, that's a different story.
I saw that first hand with two of my fellow wrestling teammates in high school who enlisted in the Marines. I was going for a Marine ROTC (although I was not selected). It came from a volunteer who used another avenue to harass students and claimed "free speech" and "free access" -- explicitly stating just like the military. She was also associated with individual who were, in many cases, older (failed several years) and protesting everything, including the Galileo launch with a RTG (which got my picture in the paper because I debate them, alone, on the scientific facts).
Because of my status at my high school as someone of unbias and a staunch Libertarian, who regularly stood up for their rights to protest (even the Galileo launch), while having a strong science background, I was often used a reference in these on-going issues. At one point I finally said it, "this woman is harassing people who have already made a contractual obligation." She was eventually banned from campus as a result of my finally pointing that out, hesitant to seemingly "take sides" prior. It was that one fact, that she was talking to students that had already made a contractual obligation that could not be undone, that finally caused me to recommend it.
All I can say is if the ACLU got behind this woman, then she's probably not an example that would embarrass them. But let's all remember it's not about "preventing people from fighting in an allegedly unjustified war." It's about free speech. It's when people make it political, and not about the individual, that it's a problem. The idea here is to help people think and make choices for themselves. It's not to make them an activist as well. I have the same problem with Bible thumpers and any other type of activist. They focus on membership and size, instead of information and thought.