It's not as if you are even given the choice to be a citizen of the U.S. Government. If you are born here, you are subject to the laws, regardless of whether they're right or not. Our government, at it's core, is fundamentally coercive. I don't have the right as a taxpayer and citizen to demand that my government not use my taxes to fund activities that I find repugnant, like warfare and capital punishment. I don't have the freedom to decide what sorts of things I put in my body.
Freedom of speech is similarly inhibited.
It's possible that every thing I say here could be monitored in some way if law enforcement decided it was in the interest of national security or some such ridiculousness. Throughout much of our century the FBI, as part of our own democratic government, compiled files about people whose patriotism and loyalty they questioned. Many of these are available now as a result of The Freedom of Information Act. People like Martin Luther King, Jr., John Lennon, etc. All of this stuff can be extremely disheartening, but I do believe that one day there really will be true freedom and democracy and we will all have the opportunity to live in an ethical society.