Surely it depends on your ideals?

An idealist is not hoping for what I want in an ideal world, but for what they want in an ideal world.

Hitler's ideals made him the perfact Nazi idealist, this does not come under your category of "things can be nicer, safer, cleaner, or friendlier than they are now".

Idealism is not about what will make the world better, it's about what will make the world better for the idealist, to the exclusion of all others.