“When there is a hurricane you can see it on a map, you have a sense of how hard the storm will hit and how long the storm will last," said Lengyel, who is chief of the National Guard Bureau. "With Covid-19, it's like we have 54 separate hurricanes in every state, territory and the District of Columbia.”

Hours after Lengyel spoke, Pentagon spokesperson Alyssa Farah announced that the administration plans to keep Guard troops under state control.

"The @DeptOfDefense is not considering federalization of the @USNationalGuard," she tweeted. "The #COVID19 response is dynamic, but at this time Governors remain in control of their states’ National Guard forces & can request additional assistance from federal Title 10 forces through @FEMAgov."

During his briefing with reporters, Lengyel made the case for keeping the Guard units under state control.

In their current state-level Title 32 status, the country's 450,000 Guardsmen can be deployed by their governor to transport medical supplies, help with drive-through testing, and assist local law enforcement with enforcing curfews and other tasks, Lengyel said. He advised against federalizing the National Guard under Title 10 — one of the options the administration had been considering — because doing so means the states would lose some of those authorities.

Under the Posse Comitatus Act, the federal government is prohibited from using U.S. troops for domestic law enforcement. This limitation does not apply to the National Guard when activated by a state's governor and operating under Title 32. Louisiana state officials deployed Guardsmen in this capacity in response to Hurricane Katrina in 2005.

When under state control, Guardsmen have "additional authorities that can assist law enforcement and they maintain their direct command and control links within their states," Lengyel said. This "makes it a faster, more rapid, more efficient response for the government and the state emergency response network to use them."

The primary reason to federalize the National Guard would be in a "World War III" scenario where additional forces are needed rapidly to go to war "with a major peer competitor," Lengyel explained. But in the case of the coronavirus, no such action is needed, which he said would cost "billions and billions of dollars."

"I think you can get everything you need more efficiently and more effectively if you leave them in a state status," Lengyel said. "There is no need right now to have 450,000 Guardsmen on duty in any given state."