THE Constitution seems clear enough. It says that Congress "shall have power to lay and collect taxes...and provide for the common defense and general welfare of the United States." But when Congress has appropriated money, must a President spend it? Yes, say most congressional leaders. No, says President Nixon.
The constitutional conflict could end up before the Supreme Court, but a clear-cut answer is unlikely. "Great ordinances of the Constitution," wrote Oliver Wendell Holmes, "do not establish and divide fields of black and white. We cannot carry out the distinction between legislative and...