True, it's fair to argue that many of them say lots of stupid stuff they'll never accomplish, but few of them have an entire campaign built around it. Every time Clinton tries to say "look, you can just march in and say this is how it's going to be, there is compromise" (a rare political truth) Sanders jumps all over it. There is a difference between what you set out as goals and what you can actually accomplish. Just because I want to clean my entire house in one day doesn't mean I can do it. Sometimes you have to start somewhere and get as far as you can. Some days you may clean the whole thing, but sometimes you get bogged down before the dishes are done. That's reality. Is it better that countries are pumping out coal or fracking? If fracking reduces emissions substantially and bridges the gap to solar - that's a good thing, maybe not perfect but good. But if you insist on solar or bust and that gets you nowhere - which is the better choice? To put it simply, walking around demanding all or nothing usually gets you nothing. So on major issues, I'll take incremental over nothing. We all wish we could wave a magic wand and get from point A to point B in one clean sweep, but that's just not how it works. Especially not in politics.