With an Arctic blast chilling the northern states, U.S. President Donald Trump tweeted over the weekend that it "Wouldn't be bad to have a little of that good old fashioned Global Warming right now!"
The apparent irony that cold weather can strike a warming world is a time-tested line for Trump, Republican colleagues on Capitol Hill and even late-night talk show hosts. Nothing diffuses a joke quite like further analysis, under which this one falls apart.
Trump's statement confuses weather, which is short-term local fluctuations that people check every morning before stepping outside, and climate, which is the long-term aggregate of everything that happens weather-wise in an area or globally. Confusing the two is like conflating a Major League Baseball slugger's lifetime batting average with a single trip to the plate, or a person's character or disposition with a fleeting mood.