The climate science is clear: it's now or never to avert catastrophe | Bill McKibben

Disastrous global heating will soon become irrevocable - but despite politicians' inaction millions are taking to the streets to fight the planet's fever

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The one thing never to forget about global warming is that it's a timed test.

It's ignoble and dangerous to delay progress on any important issue, of course - if, in 2020, America continues to ignore the healthcare needs of many of its citizens, those people will sicken, die, go bankrupt. The damage will be very real. But that damage won't make it harder, come 2021 or 2025 or 2030, to do the right thing about healthcare.