Tell me, if you went to a Uni in your area and said "I would like to speak about how much I like balloons for two hours at a University sponsored event", would you expect them to say yes? Assuming you are sane, the answer is probably no. Why is that? Because there is no universal right for a University sponsored platform. There is no expectation of universal access here. A Uni doesn't simply provide a platform to whoever asks, there are a number of factors which go into making the decision of who may partake. You are focusing on one of those (political leaning), however, in assuming true freedom, you have to similarly account for all of those. You cannot argue that freedom of speech should give those on the right a platform at a University without similarly arguing that freedom of speech should give literally everyone a platform at a University, no matter what they have to say (or don't have to say).
And in my opinion, that idea is incredibly ludicrous.
Taking your hypothetical example into account, and integrating it into what's going on right now, my reply to the school would be, 'well I'm fully aware that you've had plenty of individuals on campus speaking about how much they like blue balloons, and I've had students ask me to come and speak about red balloons, because they either aren't interested in blue balloons, or they are curious and would like to know what red balloons are like.'
If blue balloons are ok and have a sizable audience, what's wrong with a sizable audience that's interested in red balloons? Are red balloons like peanut butter and for the safety of the few who are 'allergic', only blue balloons are permitted?
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