> multiple people broadcasting onto the same frequencies would ruin it for everyone.
Let's see who is conflating things. Enforcing the rights of frequency band owners has nothing to do with needing an FCC. All you need is regular enforcement of property rights. If someone has a right to use a frequency and someone else is disturbing that right then they will be prosecuted according to the law. Just like with land.
Ok, so what's the problem with the FCC? If I find a frequency that is unassigned (no current owner) and unused (no current squatter) then I can't start using it (homesteading) and I can't acquire property rights from mixing my labor with it. Instead, I have to go to the FCC and hope they approve me for broadcast license; and they will approve it or not depending on their political opinions about what I am going to be saying in that frequency. Also, broadcasting licenses are non-transferable so I can't buy your license even if we both agree on the transaction - the FCC needs to vet me first. This is a huge problem, as I hope you can see. That means the government must approve of my message before I can say it. It is an impingement on free speech. If people could yell high enough that others could hear without needing radio waves (websites = yelling high enough) then the government would want to curb that too (and indeed it is, with Net Neutrality).
Hopefully this clarifies my point.
> why haven't they started censoring telephone conversations
Because it is usually two-way, with both parties usually being part of the government's tax farm (ie. regular folks), in which case there's more in it for the government if they record our conversations than if they censored it (which would make people weary of communicating, and harder for the government to spy on its citizens).
Also the telephone is usually one-to-one communication, not one-to-many like radio stations, tv channels and internet websites. So the damage from unwanted information getting out to the public at large easily, and therefore the need to censor it, are almost non-existent.
And just to clarify for the impolite person below, Karunamon:
By censorhip I don't mean censoring existing stations. I mean disallowing stations from ever coming to be, because the FCC disagrees politically with the folks asking for a broadcast license. The public at large ends up losing out, because they have only government-approved stations to listen to, and never get to hear truly dissenting opinions. This is curbed free speech.
As for the excuse that one must get a license to prove they are technically capable, a technical test would suffice, just like a technical test suffices for handling guns. The government can't choose not to give guns to people of certain political opinions, but it can choose not to give broadcast licenses to those people. That's what's wrong. If you own a frequency and it is disturbed you have the right to sue and collect reparation from the person who disturbed your property. The FCC is not needed for this just as there's no FCC for land - if someone disturbs your land you call the police.