Try showing a palestinian flag or an anti monarchy piece of paper in the very civilised and liberal UK and see what happens to you in the totally free western world.
There's no evidence in that article that anyone was arrested for flying the flag of Palestine. It's about protests in favour of a specific proscribed group. I'm as pro-Palestine as they come but linking to that article to support the claims made above is just dishonest.
I read it and responded accordingly. Your point was about the flying of a flag in the UK. You followed this up with an article about people being arrested for supporting a proscribed organisation, not for the flying that flag which we both know many people are doing every day
If you would like to make a further point then please do so.