New U.K. Chancellor Kwasi Kwarteng fired the opening shot Friday in Prime Minister Liz Truss’s battle for economic growth, and the pound promptly lost as much as 2% of its value against the dollar. One ignores market signals at one’s peril, but in this case it’s worth parsing who is signalling what about whom. This is a pro-growth agenda that is very different than the tax-and spend Keynesianism that has dominated the West’s economic policies for nearly two decades.
Ms. Truss campaigned for her job this summer on a promise to jolt the British economy with a supply-side revolution. And she is showing she means it. Mr. Kwarteng’s announcement, billed coyly as a “mini budget,” constitutes the largest package of tax cuts in 50 years.