Which reminds me of one of my biggest objections to the US constitution: constitutional amendments are done simply by getting a bunch of legislatures to agree to 'em, rather than by holding a referendum as in Australia.
My state, like a few others in the US, has voter initiatives that become constitutional amendments. The last one that made the news was the one that made it illegal for me to get married.
Another initiative from a few decades ago is a major part of why California can't raise enough money to fund itself now.
So yeah, I'm not a huge fan of ballot initiatives.
Compare that to 11 amendments to the US Constitution over the same period (1901 onwards) - two of which I'd point out dealt with the introduction and repeal of Prohibition (which I'd say qualified as a "swell of public sentiment").