When progressives propose new or expanded social programs, they face intense media scrutiny bordering on harassment over how they intend to pay for these programs. Republicans proposing tax cuts don’t face anything like the same scrutiny; they are seemingly able to get away with blithe assertions that tax cuts will pay for themselves by boosting economic growth, even though every single piece of evidence we have says that this is nonsense.
— Paul Krugman brings the truth in a New York Times column about the IOKIYAR principle (Debt, doomsayers and double standards)