Can psychology illuminate and transform our collective reluctance to address global, social and environmental challenges? Can it also help us as humans, to foster dialog with our unlikely allies and help people get along? Or is this simply too unrealistic?

Illuminate, yes.
Transform, no.

Most of what it can do is already being done, both by those trying to advance the public interest and by those trying to advance their own commercial interests against the public interest.

Odd question. Psychology can do nothing unless used by people. What are you suggesting: brainwashing to induce induce people to 'care' about things you think they should care about?

Most Psychology is severely flawed and has created more problems than it cures. At its root it denies the adamic nature. This results in numerous kids being prescribed drugs for bad behaviour. Have you not noticed that that with huges increases in the mental health budget the problem is now worse than ever.

Who's "us"? What's the collective? Where are the crises?
I've got the solution in a nutshell, how about everybody keeps their nose out of other people's business and concentrates on what's immediately in front of them?

Runner, you have no idea what you are talking about.
Psychologists can't prescribe drugs, as they are not licensed to do so.
Wrong again.