I think that people often misread the First Amendment.
Here:
Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof; or abridging the freedom of speech, or of the press; or the right of the people peaceably to assemble, and to petition the Government for a redress of grievances.
Twitter is a private company. The First Amendment protections do not apply to its customers. It directs the US Government to avoid restricting certain rights of its citizens (but even those rights have limits). If you posted that you liked the color pink and Twitter took objection, they, assuming that they'd posted the fact that this was in their discretion, could delete your account. Advocating murdering the Speaker of the House of Representatives is another matter entirely. There's a line that can be crossed that constitutes illegal utterances: inciting riot, advocating violence, suggesting that someone go murder a doctor and publishing their home address, those sorts of things are not protected under the First Amendment. It's one thing to say you hate Nancy Pelosi, but quite another thing to encourage others to murder her.
Our biggest problem in the US is not freedom of speech being limited, it's domestic terrorism and a flowering of extreme right wing militias. These are generally self-described disenfranchised whites (mostly male) who are devoted to stifling free speech and free exercise of your right to be a Jew, a Muslim, a member of a non-white race, a member of the LGBTQ community, or a political liberal. They are misogynistic and opposed to equal rights among those who are not "free white men." Normally, they'd just go online and grumble, get ugly tattoos and hang out in bars, drive motorcycles (usually Harley Davidsons as you wouldn't want to ride some kitty Euro bike like a BMW), and post ugly memes of powerful women like Hilary Clinton or Nancy Pelosi.
But in recent years, they've gotten a bit more lawless, attempting to kidnap the Governor of Michigan (with murderous intent), illegally appropriating or occupying Federal lands, and in recent days, placing pipe bombs in the offices of the Republican and Democratic National Committees in Washington, DC. The actions on Wednesday resulted in the deaths of two police officers and 4 civilians (the latter were involved in the insurrection). They also refuse to wear masks (as COVID is a "Democratic hoax"), and do not recognize the government's right to establish sensible gun control laws.
Radical Islam is less of a threat than these jokers any day of the week. It's terrifying to see the number of right wing zealots photographed in Wednesday's insurrection who are wearing pro Nazi teeshirts. "6MWE" (six million wasn't enough--i.e. "kill more Jews"), "Camp Auschwitz", etc.) It staggers the imagination. These are people who have no idea how the government works, who know nothing about the Second World War, and know only what they hear on Fox News or what they read on the OANN.com (one America news network) network.
Out of curiosity, I set up a Parler account this past week, to see what this right wing twitter clone was about. I read tons of posts about planning for Wednesday's rally in D.C. There were gleeful bits of advice filled with all the enthusiasm of children planning a Christmas party. The party featured lots of tips about how to infiltrate illegal firearms into the District of Columbia (that has some of the country's tightest gun restrictions), and the like. It's not hard to imagine that the chaos that ensued was planned and put together on a national basis with a clear intent to cause harm.
I can't wait for this to be thoroughly investigated. In my humble opinion, Trump should be in jail. He has blood on his hands. Lying to millions of people has consequences.
I used to think that Nazi Germany was something that happened to those quaint weird Germans and in Central Europe a long time ago. As a visitor in the 1980's, I saw the traces of shrapnel across facades in cities in Hungary and the two Germanies. The odd racial and nationalistic policies of the Third Reich seemed like the extremist symptoms of governments that, for one reason or the other, didn't have their act together. Well, I was wrong. America is just as, if not more, vulnerable.