In the U.S. and much of the rest of the civilized world, you have rights. This includes the right to not self-incriminate (in the U.S. that's the 5th amendment). In general, except for very specific and limited circumstances, U.S. state and federal government actors cannot compel speech (telling your encryption keys is compelled speech).
The U.K. is fast sliding down the slope to being a dystopian police state. The idea that you can be jailed for refusing to provide encryption keys (except for really specific, narrowly-defined circumstances) is something that should induce nausea. I feel for you and your country, you accomplished such great things.
I just saw that president Trump is thinking about prescribing 'Antifa' as a terrorist organisation and saying that he's 'not sure' their 1st amendment rights should apply.
I'd be a little more concerned about the state of US at this point.
I don't actually know what "Antifa" is, if it is in fact anything specific (rather than, e.g., a banner used by many and disparate groups--maybe that was your concern?).
What I did mean is that declaring certain organizations to be terrorist organizations (HAMAS, Al-Qaeda, etc.) seems to be well within the remit of the executive branch.
Antifa is not an organization. It's an ideology. There are groups that call themselves anti-fascists, which have different views and methods, and there is no HQ they answer to. Just like MAGA.
Another example: banning zionism/antizionism or banning racism.
It can't work like that.
The focus has to be on criminal acts committed by individuals, regardless of their ideological affiliation.
Banning an ideology would be a direct and fundamental attack on the 1st amendment of the constitution.
It would lead to "guilt by association." A concept the Supreme Court has found to be unconstitutional. (NAACP v. Alabama (1958), Scales v. United States (1961), Noto v. United States (1961), United States v. Robel (1967), etc.)
The U.K. is fast sliding down the slope to being a dystopian police state. The idea that you can be jailed for refusing to provide encryption keys (except for really specific, narrowly-defined circumstances) is something that should induce nausea. I feel for you and your country, you accomplished such great things.