The UK is one of the Western democracies without the protections you're talking about (no written constitution, no ability to bind future parliaments, law passed by a simple majority of parliamentarians, first-past-the-post and strong third-parties leading to parliamentary majorities with ~35% of the vote) but has one of the longest and proudest histories when it comes to freedom and liberty.

Mob rule is always a risk but it's often better than rule by an out-of-touch elite.