Had he not been restricted, including in deploying a quick-reaction force, he said he would have been able to send 155 soldiers to the Capitol hours earlier. “I believe that number could have made a difference,” he said. “We could have helped extend the perimeter and helped push back the crowd.” Most vivid was his description of readying troops and then having them sit on buses waiting for a green light from the Pentagon — this while the Capitol was being ransacked, and frightened members of Congress and their staffs were hiding from the mob.

Robert G. Salesses, the senior Defense Department official testifying on the department’s behalf, had not been involved in any of the Jan. 6 discussions. Not surprisingly, his explanations about the chain of the command and assertion that only the defense secretary could approve troop use for civil disturbances left many members unsatisfied. As well they should be. What happened Jan. 6 was an abomination that must never happen again. Efforts to find out exactly what went wrong have so far mainly produced a lot of finger-pointing and a lot more questions. That underscores the need for Congress to appoint a bipartisan commission to investigate the events of Jan. 6.