The deck is stacked. They only have to win once, and it's law. You have to win over and over every time it's introduced.
It's analogous to information security.-
PS. Maybe there's something there ...
Is this really true, though? Couldn't you pass a law specifically banning the thing you don't want to happen, so any future law that contradicts it needs a supermajority to pass or something?
Heinlein in The Moon Is A Harsh Mistress proposed a bicameral legislature, where one half needs a 66% majority to pass a law. The other half’s only job is to repeal laws, which they can do with a 50% majority.