I don’t recall Dems being “glum” in the 70s and 80s. They were righteous and angry in the 70s, histrionic in the 80s.
I think it’s a mistake for Zakaria to characterize Reagan’s perspective as “optimism”. Reagan wasn’t a meliorist.
And although I did feel a few moments of optimism for the US under Reagan, Bush I, and even Bush II, I have long believed that, having cut loose of Constitution moorings, our political system was living on borrowed time.
It’s a much different country since Reagan’s time....look at the demographics, and now look at who controls our media.