Was he being sarcastic?
No. Krugman is a leftist piece of shit. He’s an economic moron that was given a Nobel prize by leftist morons. They really are economic idiots. They believe Keynesian economics and Modern Monetary Theory work despite failure after failure after implementing policies for both. The simple acid test is that Krugman is in the employ of the New York Times. You can be assured Krugman is not joking and he seriously wants the destruction of America.