They should but will likely never see a day in jail. The courts are usually too sympathetic. The next best thing is to shoot them with tasers or bean bag shotguns. Sure, they will get off in court but they will have a reminder of their actions.
In reality, they are not climate activists. They are anarchist thugs. The world needs to start treating them as such. Protest peacefully all you want. Do damage, harass people, traffic or commerce, and they should be made to feel a heavy handed response even if there is no jail time. Public ridicule would also be a good thing.
Pepper spray would work well too.
Absolutely!!!!!