Good for him/them. I'd been in the Marine Corps for four years before I went and I was immune. I locked horns with nutty PhDs who thought those letters made them god almighty. I didn't care who booed, jeered, or disagreed.
I inoculated my two children and both made it through college with their values in tact. They were fully armed with every leftwing idea imaginable and more importantly, how to counter them. No yelling. No emotion. Just clear facts stated politely but firmly. Most enter with a predisposition toward leftwing ideas but many others are converted by the constant leftwing undertone but it doesn't have to be that way.