Would You Kill Hitler to Save the Planet?

Just thinking about stuff after reading this:

If the Arctic becomes six degrees warmer, then half of the world's permafrost will likely thaw, probably to a depth of a few metres, releasing most of the carbon and methane accumulated there over thousands of years, said Vladimir Romanovsky of the University of Alaska in Fairbanks and a world expert on permafrost.

Methane is a global warming gas approximately 25 times more potent than carbon dioxide (CO₂).

That would be catastrophic for human civilisation, experts agree.

As a culture, we are apparently quite content to let ourselves be ruled by a business-government-media elite that will spend (in Canada) over $10 billion propping up narco-pedophile-torturers in Afghanistan, but which refuses to acknowledge the real crisis of global warming.

What is to be done?