This is a straw man argument.
Should a person, or group, be free to promote white supremacy, male superiority (sexism), homophobia  and racism in a speech that will incite violence against those who whose skin is not white, women, and gays?
Should a modern-day fascist be given the freedom to perform apartheid and genocide against millions of people because of their religion -- like Hitler did the Jews?
Your freedom ends when it takes away (through laws, coercion, and violence) the freedom and equality of others. The protesters at U.C. Berkeley last night were fighting against the forces who believe in the superiority and supremacy of the white, straight male who is best suited to rule over his household and all of mankind on a global basis. Here's the difference:
The protesters were fighting for the freedom and equality for everyone with no regard to gender, skin color or sexual orientation.
Your freedom of speech argument is to provide "freedom of speech" protections for a man to speak and incite a crowd of young adults about allowing freedom and equality to a limited, select group ... white, (straight) males only. All others are to be subject to domination, persecution, and all kinds of violent acts -- all of which will be protected by the laws of the State.
The freedom and equality of all trumps your freedom of speech for one ... every time.
We will not allow white supremacy, sexism, racism, and homophobia to be the norm. As a result, Milo's speech had to be shutdown. Mission accomplished.
The minor violence to property at U.C. Berkeley doesn't hold a candle to the violence against people incited by speeches by Milo and other White Supremacists.
We do not fight fascism because victory is assured. We fight fascism because we will never surrender to tyranny.
 Milo claims to be gay. As photos document at U.C. Berkeley last night, there isn't a gay on the planet that believes that line of excrement for a second.