As the United States surpassed 1 million known coronavirus cases — with true infection levels expected to be much higher — a retired four-star army general and consultant to the city of Boston said the country needs to come together to get through this crisis.

Retired Army General Stanley McChrystal told Jim Braude on WGBH News’ Greater Boston Tuesday that President Donald Trump’s decision to put most of the responsibility for testing, equipment and social distancing orders on individual states is the wrong way to go.

“If you’re gonna defeat an enemy, what you try to do in the military is break them into piecemeal and destroy them that way. If you don’t want to get defeated, you unite,” he said. “The United States ought to be 50 united states facing this together.”

McChrystal likened the coronavirus crisis to past crises he faced as a commander of the Joint Special Operations Command during the Iraq war.

“Al Qaeda in Iraq, which we first faced starting in 2003, was an amorphous, virus-like enemy … it was nowhere, and it was everywhere — a little bit like COVID-19,” he said. “And it takes a whole-of-society approach to fight it.”

But McChrystal, whose consulting firm was brought on by Mayor Marty Walsh in March to help oversee the city’s coronavirus response, said Boston will push on in the absence of strong federal guidance.

“We always fight the war we have — in this case, COVID-19 — in the conditions we have it,” he said. “We take into account where leadership is, where it isn’t and we focus and try to get the job done.”

The retired general, who was otherwise loath to criticize Trump, pointed to the leadership he’s seeing from state and local leaders — including Mayor Walsh.

“What I’m looking for in a leader is candid integrity. I’m looking for leaders who show real empathy for the people who are affected by this and those who can also give us some inspiration for the future,” he said. “One of the great things we’re seeing right now, is we’re seeing leadership emerge at the mayoral level, at the governor level from across the nation.”

The retired general said that this crisis will be a defining moment for all Americans.

“I think that this is going to be the memory of our generation. It’s going to be what happened before and after. All of us are going to say, ‘What did we do during the big pandemic. Did we live up to our expectations of ourselves?” he said. “I think that’s the great opportunity.”