WASHINGTON (Reuters) – U.S. Defense Secretary Lloyd Austin defended America’s response to the war in Ukraine on Tuesday during a heated exchange with a Republican lawmaker who accused the Pentagon of over-estimating Russia’s military capability. “Has it occurred to you that Russia has not overrun Ukraine because of what we’ve done? And our allies have done? Have you ever even thought about that?,” Austin asked rhetorically to Rep. Matt Gaetz during testimony to the House Armed Services Committee. Austin and other U.S. officials say U.S. support to Ukrainian forces, along with Ukraine’s strong …