My latest column at The Week is the only column published anywhere today that is not about Donald Trump Jr.:

President Ronald Reagan famously used to discomfit his advisors by bringing up a favorite thought experiment. What, he wondered, would the nations of the world do if extra-terrestrial aliens invaded our planet? Wouldn’t we put aside our differences and unite against the common threat? And if that is true, then shouldn’t we put aside our differences now, to unite against that which threatens all of life on earth, the scourge of nuclear weapons? . . .

Of course, Reagan’s vision never came to pass. The Cold War ended, not because America and the Soviet Union put aside our differences but because the Soviet side collapsed. Far from abandoning nuclear weapons that they could ill afford, the Russian Federation has clung to them as a vital signifier of superpower status, while the United States has, under Bush and Obama and now Trump, explored ever more-seriously using them on the battlefield. Worst of all, nuclear technology is now in the hands of a regime as terrifying as North Korea. If the fear of a general nuclear exchange has receded considerably, the prospects of international cooperation to actually end the threat feel further away than they were at the height of the Cold War.

I was thinking about this history in light of the much-discussed recent doom-crying article on climate change by David Wallace-Wells for New York magazine.

Wallace-Wells’ premise in writing the article is similar in its way to Reagan’s: that if people understood the nature and scope of the common threat, they would unite against it. Most people probably don’t realize just how catastrophic the consequences of climate change could be, just as most people probably didn’t realize that mutually-assured destruction really did mean that the human race itself was at risk if deterrence ever broke down. While much of the press since Wallace-Wells’ article came out has cautioned that the worst-case scenarios are unlikely and that real progress is actually being made, it’s also true that the composition of the atmosphere has already changed enough that some serious consequences are already baked in, and that predictions get harder the further out into the tail of the probability distribution we get. Even under more hopeful scenarios, the potential consequences of climate change are severe enough to outweigh virtually any of the petty concerns that dominate our politics.

So why can’t we unite against this threat?

Read the whole thing there for my answer.