Coolidge was a pragmatist. He didn't start out with a tax theory. But he observed over time that lower tax rates sometimes brought in extra revenue. The success of his and Treasury Secretary Andrew Mellon's experiment with rate cuts has been obscured by our modern history books.
Amity ShlaesCoolidge cut the budget, and even better, cut it during peace and prosperity. He left a federal budget lower than the one that greeted him when he arrived in office. He managed to freeze or cut the budget over more than five years in office. If you look at charts of presidents - Nixon, Ike, and Reagan - you see them failing on this score.
Amity ShlaesEurope unified its monetary policy through the euro before it unified politically, therefore sustaining member countries' abilities to pursue the kind of independent fiscal policies that can strain a joint currency.
Amity Shlaes