A general discussion of the moral issues of which kinds of protest are legitimate, then applied to the case of protesting by blocking highways.

This discussion makes sense, in its narrow framework. However, treating the Just Stop Oil protests in isolation, ignoring the deadly threat they confront, leads to wrong conclusions.

Global heating and the resulting climate breakdown are already causing millions of deaths. This year, 200 million deaths are predicted. The UK government has pledged to help stop global heating but is not taking much action. Can you seriously argue that blocking highways in desperation to pressure the state to carry out its mission is morally wrong?

Blocking highways seems to be a self-defeating method, but that is a different kind of issue.