If you don’t like America, please speak up so we can work to improve it. The rights to free speech and press don’t exist to protect the views of the majority or those for whom everything is dandy: those people inevitably have a voice. These rights exist to protect the views of the disenfranchised and the dissatisfied, to prevent oppression. Voicing one’s dissatisfaction is the America established by those documents; I would hardly call it “ridicule” to use the word “radical.”
It’s OK to end a question with a preposition. It’s just so satisfying to say “whom.”