Commentary Federal Reserve (Fed) policymakers have made a change. Chairman Jerome Powell announced only days ago that the nation’s inflation problems impel a more restrictive monetary stance. Accordingly, the Fed has ended its long-held practice of directly buying securities in financial markets—what the Fed calls “quantitative easing.” Policymakers have also raised the benchmark federal funds rate by 0.25 percentage points to 0.5 percent. These changes were widely expected. So was the Fed’s warning of more rate hikes to come and a kind of reverse quantitative easing in which policy absorbs inflationary liquidity from the system by selling from the huge asset portfolio the Fed amassed during the long period of quantitative easing. All this is a relief for the inflationary concerns of Wall Street and Main Street. But still more helpful was something few expected. The Fed’s public statement accompanying the policy shift described today’s inflation as the result of …