I love the Political Party mechanics of ES2, but I'm seeing some behavior that I don't understand.

Early on, I had a long war with the Cravers. Obviously, this lead to a rampant growth of Militarist support, as I constructed and destroyed a lot of ships. However, after the war, I was unable to get Military support to decrease at all. I sold all but a couple ships, I fired my military Hero, I bought Peace with every neighbor, and researched only Science techs. Military support held steady around 80%. Anyone have guesses why this would be?

Very little navy...

...and nothing but Peace.

Eventually I switched to Dictatorship, so that I could use the Scientist Propaganda continuous improvement. This worked as expected, with increasing returns over time. I intended to spend a few turns getting Scientist support above Militarist, and then switch to another government. When I en-queued another building, I expected Militarist support to freeze. Instead, it instantly snapped back to its value from before I did any Propaganda.

Is this working as intended? If so, what's the point of Propaganda?

Militarist support snaps back