It's in everyone's best interest that roads, especially main ones, remain open
Specifically the current 'protests', be it blocking roads or criminal damage, do not serve any constructive purpose at all. They are carried out by the 'usual suspects'. They could organise a massive gathering in Hyde Park (and similar in towns throughout the country), for example, that would get huge media coverage as well without causing problems, ah but that wouldn't be 'direct revolutionary action'...
In the US, we have other disruptive events such as marathons; parades; Presidential convoys. All of which can disrupt main roads and aren’t even protected.
Specifically the current 'protests', be it blocking roads or criminal damage, do not serve any constructive purpose at all. They are carried out by the 'usual suspects'. They could organise a massive gathering in Hyde Park (and similar in towns throughout the country), for example, that would get huge media coverage as well without causing problems, ah but that wouldn't be 'direct revolutionary action'...