WASHINGTON — Governors' warnings of life-threatening shortages of ventilators have emerged as a flashpoint between President Donald Trump and the states as the coronavirus crisis deepens.

"Some states have more ventilators than they need," Trump told a news briefing Saturday. "They don't even like to admit it. They'll admit it when everything's over but that doesn't help us very much.“

Governors in hard-hit states like New York, Michigan and Louisiana say doctors could be forced to make life or death decisions about who will get ventilators and who won't if hospitals starting running out of the machines when the peak of the crisis hits.

Louisiana Gov. John Bel Edwards has said his state is expected to exhaust its supply of ventilators by April 6. Though Louisiana has received some ventilators from the national stockpile, Edwards said his state still needs thousands more.

New York Gov. Andrew Cuomo has estimated his state will need as many as 30,000 ventilators and could start facing shortages by the middle of next week.

Cuomo dismissed the suggestion that he was overstating the needs. He said New York was prepared to pay for 17,000 ventilators it had ordered on its own but didn't get them because of competing demands.

"We were not looking to spend a penny that we didn't have to spend," Cuomo said.

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Without naming a specific governor Trump said Saturday he was frustrated that some states that have already received ventilators from the federal government were insisting they needed more.

"And then the media meets with the governor and they say, 'Oh, you got more. Well, it's not enough. The president should have sent more,'" Trump said, adding "that's politics."

The tensions between governors and the Trump administration grew this week when Jared Kushner, a senior White House adviser and the president's son-in-law, referred to the federal stockpile of medical supplies as "our stockpile."

"It's not supposed to be states' stockpiles that they then use," he said.

Trump has said the federal government is ready to help the states but needs the "flexibility of moving the ventilators" to virus hot spots. He and his aides say the administration will mobilize the equipment to areas where it's most needed days in advance but they're also urging states to tap their own stockpiles and do what they can to obtain their own supplies.

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Several governors want the federal government to use its clout to buy more ventilators. The Federal Emergency Management Agency could then distribute to states in the greatest need, the governors argue.

"Why would you create a situation where the 50 states are competing with each other and then the federal government, FEMA, comes in and competes with the rest of it?" Cuomo asked.

Illinois Gov. J.B. Pritzker and Michigan Governor Gretchen Whitmer have also expressed frustration over competing against one another – and the federal government – in bidding for supplies in the private market, which has led to price-gouging.

So how many ventilators are likely to be needed, how many are there now and why are they in such short supply? Here's an overview of what led to the problems and the debate over how to solve them.

How many ventilators are available?

Trump has declared the U.S would produce 100,000 ventilators in 100 days and told reporters Thursday that 11 companies were behind the effort to expedite production. While General Motors and Ford have said they would manufacture ventilators, it wasn't immediately clear what other companies were producing the machines.

Most of the 100,000 ventilators Trump promised to have by June will not be available until the end of the month at the earliest, FEMA officials told the House Oversight Committee this week.

FEMA said there were just 9,500 ventilators in the national stockpile, with about 3,200 expected to be added by the week of April 13, according to documents from the agency released by the committee's Democrats.

The U.S. coronavirus crisis is projected to peak by the middle of April, when nearly 32,000 ventilators will be needed to address the outbreak, according to data from the Washington Institute for Health Metrics and Evaluation.

FEMA acknowledges "that the Strategic National Stockpile (SNS) alone could not fulfill all requirements at the State and tribal level" in response to the coronavirus pandemic, according to an agency spokesperson.

FEMA officials have told the House Oversight Committee the demand for ventilators "outstrips the capacity" of the national stockpile as well as the 1,065 machines donated by the Department of Defense.

As of April 2, FEMA officials have shipped 8,100 ventilators from the national stockpile, a FEMA spokesperson said, adding that the agency is expediting critical medical supplies from the global market to medical distributors across the country.

Six flights carrying medical supplies from Asia have arrived in the U.S. since March 29, including two flights that arrived Chicago and Columbus, Ohio, early on Friday, according to the FEMA spokesperson. The agency has scheduled 27 additional flights through April 18.

The medical supplies will be given first to medical distributors in areas of greatest need and the remainder "will be infused into the broader U.S. supply chain," the FEMA spokesperson said.

FEMA also points to the $16 billion allocated to build up the stockpile in the $2 trillion stimulus package passed by Congress last week that will help address the shortage.

Why is there a shortage?

The Strategic National Stockpile, which is managed by the Department of Health and Human Services, consists of several secretly located warehouses across the U.S. that contain emergency medical supplies.

Former Wisconsin Gov. Tommy Thompson, who served as health secretary under former President George W. Bush and oversaw the response to outbreaks of anthrax, SARS and Monkeypox, said the number of warehouses was expanded to 12 from eight after the 9/11 attacks.

Thompson, who said he offered a federal plan for preparation for a pandemic before he left office, said Congress failed to appropriate funding to replenish the depleted stockpiles over the years.

"They were maintained, but they were not expanded," he told USA TODAY. "I think it was lack of attention. I don't think you blame the governors. I don't think you blame the president. I think that everybody neglected filling these sites with what was needed."

Greg Burel, who served as head of the SNS for more than 12 years before he retired in January, said the stockpile was not initially designed for pandemic influenza but Congress began investing funds in preparation for such an event in the early 2000s.

"We always knew that even then, it wasn't as much as some of the models suggested we would need if it was a 1918 sort of an event," he said, referring to the flu pandemic of 1918. "Even with the pandemic influenza money, it was going to be almost impossible fiscally, to stockpile our way out of that kind of a problem."

Burel said Congress never saw fit to fund the replacement of materials exhausted during the the 2009 flu epidemic, which played a hand in today's unfolding coronavirus crisis. He added that local and state health departments lack the funding needed and the private health care supply chain operates in "just-in-time" basis that hinders any sort of wide-scale response to a pandemic.

'We're not an ordering clerk'

Trump has said federal government's stockpile can help the country through the crisis but has also criticized states for having "insatiable appetites" for equipment and not doing enough to build their own supplies.

“States should have been building their stockpiles,” he added. “We’re a back-up, we’re not an ordering clerk,” he said.

But the existence of the stockpile is aimed directly at helping states, according to Josh Gotbaum, a former assistant secretary of defense for economic security and executive associate director for Office of Management and Budget under former President Bill Clinton.

"The whole purpose of emergency stockpiles is to protect the nation in an emergency. Even if the stockpiles are inadequate, they still must be used for the entire nation," he said. "It's not to make sure there's enough ventilators for the Army, Navy, Air Force and Marines. The Defense Department already takes care of that."

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Cuomo said Friday the government should send more ventilators and medical supplies that New York could then redeploy to other hard-hit localities where demand is surging.

"What is the alternative to the crisis that we see looming nationwide?" he said. "New York is in crisis. Help New York and then pick up the camp and go to the next place as this rolls across the country."

Thompson said while Cuomo and other governors are rightly focused on their states, Trump has to assess where the life-saving machines are needed most across the country.

"The stockpiles are federal...the president is responsible for all the states," Thompson said. "So he's got to make that tough decision."

Can Trump use wartime powers to get more ventilators?

Trump has shown ambivalence about using the full authority of the Korean War-era Defense Production Act to compel private companies to make ventilators, masks and other equipment. He has at times likened the wartime authority to nationalization of private industry and invoked Venezuela's economy as an example of the dangers of the approach.

While Trump announced a week ago that he was activating the DPA to force General Motors to manufacture ventilators for coronavirus, the administration had not formally ordered any machines as of Thursday, USA TODAY has learned.

Trump this week announced a fresh request to Secretary of Health and Human Services Alex Azar to use the act for several other companies, including General Electric, Hill-Rom Holdings, Medtronic, ResMed, Royal Philips, and Vyaire Medical.

But the latest order provided no more detail on how the government would compel those companies to make ventilators than the order targeted at General Motors. The order also did not clarify how many ventilators the administration is requesting.