This is not true at all. More money stays in the productive centers of the economy. This leads to more investment and growth, more creation of wealth and, ultimately, even higher tax receipts to the government, even at these lower rates. A weak economy needs more fuel. Money is the fuel.
Tax cuts enable people to keep more of their own money.
They spend it, invest it and thereby strengthen a weak economy. These are very elementary, real-world concepts. Perhaps the fact that the Doonesbury cartoonist doesn't understand them might make people question what else he may not understand. Enter words describing a concept or keywords.