On his first full day in office, President Biden signed an executive order to boost the availability of coronavirus testing. Five days later, standing in the White House with his health advisory team by his side, Biden called the fight against covid-19 a “wartime effort” and pledged that tests would be widely available.

In early September, amid the delta variant surge, Biden reiterated the promise that “every American, no matter their income, can access free and convenient tests.”

Now, nearly a full year into Biden’s term, as the virus has mutated its way through the Greek alphabet to the omicron variant, testing is in short supply in many places, leaving frustrated Americans waiting in long lines for tests — if they can get them at all.

That is feeding into a wave of concern, despondency and in some places near-frenzy at the likely approach of yet another spike in a pandemic the country has battled for nearly two years. This late-December disarray — crowded testing sites, empty drugstore shelves — is raising fresh questions about how Biden and his team have executed on his pledge to defeat the pandemic.

Drivers lined up at coronavirus testing sites across the U.S. amid the omicron surge. (The Washington Post)

“We’re going from emergency to emergency. We need a strategic plan, and executing on the strategic plan and just making it happen,” said Ezekiel Emanuel, a physician and bioethicist at the University of Pennsylvania who was on Biden’s covid advisory team during the transition. “You need a general getting all this done.”

White House officials acknowledge that not enough has been done to secure tests and are scrambling to change that amid holiday travel and the onset of the highly contagious new variant. Blaming the shortage on an unforeseen omicron-driven spike in demand, they are ordering an additional half-billion rapid tests and setting up federal testing sites around the country.

Omicron is the fifth coronavirus variant of concern and is spreading rapidly around the world. Here’s what we know. (Luis Velarde/The Washington Post)

“I don’t think it’s a failure,” Biden told ABC’s David Muir on Wednesday. “You could argue that we should have known a year ago, six months ago, two months ago, a month ago.” The president added that he now wished he’d “thought about ordering” the 500 million extra tests two months ago.

Health experts and former administration officials warn that even with Biden’s renewed focus on testing, the ramped-up supply will not meet demand. The new tests will not begin to be available until sometime in January, but it is not clear how long it will take for all half-billion to be ready — and it could well be after the omicron wave peaks.

Health experts estimate that billions more kits — not the half-billion ordered by the White House — will be needed if Americans are to use regular testing as a pathway for returning to normal life. The numbers add up quickly: If 330 million Americans were tested twice a week, for example, more than 2.5 billion tests would be needed each month.

White House officials have not said that such frequent testing would be the new normal, and they declined to say how many tests they believe are needed to meet the demand.

But many experts contend that frequent testing is a crucial pathway out of the pandemic.

“If you take a view that we’re going to need to test — probably, for most people — every day for a couple years, then you think very differently than ‘I just need to have people test themselves for the next six weeks to get through the current wave,’ ” said Bob Kocher, who served on President Barack Obama’s National Economic Council official and advised California Gov. Gavin Newsom (D) on his coronavirus response.

Kocher said he believes Americans might need to test as often as once a day, but he acknowledged that is not the consensus. “Many people share that view,” he said. “But it could be wrong.” Others say that weekly or twice-weekly testing is needed.

John Koval, a spokesman for Abbott Laboratories, which makes rapid coronavirus tests, said the company will increase production to 70 million tests in January and can continue to add capacity. “We’ve always said testing must work together with vaccines, and that frequent testing is what’ll keep workplaces open, get people traveling, keep our kids in school and make sure the economy doesn’t take unnecessary hits,” Koval said.

The company drew the ire of the Biden administration over the summer when it destroyed millions of rapid tests and laid off workers amid a lull in demand. Biden officials said they were not aware that Abbott planned to take that step.

Health experts agree that the country is far from having enough tests for a sustained, widespread testing routine. The current shortages, they say, show that the virus has again outmaneuvered Biden’s policymakers.

“This is a failure of imagination, and failure of leadership is in large part why we’re here,” said Leana Wen, a public health professor at George Washington University and Washington Post contributing columnist. “The Biden administration did a great job with vaccines, but they should have done just as much with testing. I’m very disappointed by their lack of focus on testing earlier, because we saw this one coming.”

The current testing shortage has origins in the opening months of the Biden presidency, according to former administration officials, who spoke on the condition of anonymity to offer insight about internal decision-making.

During that early period, aides said testing was the major priority and was viewed as a key element in getting the country back to normal. Senior officials throughout the government were intently focused on expanding access to tests, with a particular emphasis on PCR tests, given early questions about the accuracy of rapid antigen tests.

But this emphasis shifted to vaccines as modeling showed that immunizations would drive down new infections, according to a person familiar with the conversations. The vaccines were performing extremely well, and Biden’s team estimated that if about 75 percent of Americans got vaccinations, the pandemic would fade out. (Currently 62 percent of Americans are fully vaccinated, according to a Washington Post tracker.)

“They were like, ‘Great. We can vaccine our way out of this thing, so we don’t need so many tests,’ ” said a former transition official who spoke on the condition of anonymity to share private conversations.

Another official, who works for the Biden administration, confirmed that account, saying that White House health aides believed that once Americans were vaccinated, few would need testing.

Some in the Biden administration did worry that the White House was being shortsighted. In the spring — as reported previously in The Washington Post — a group of health-agency officials approached the White House to urge the purchase of millions of rapid tests, according to five senior administration officials who spoke on the condition of anonymity to share internal discussions.

They warned that without government intervention, the kits would remain hard-to-find and exorbitantly priced. The White House never followed up on the proposal.

In May, updated guidance from the Centers for Disease Control and Prevention affirmed the idea that testing did not need to be a major part of the country’s response to the coronavirus. The new CDC directive advised Americans that if they were vaccinated, they would not need to take tests unless they were experiencing symptoms.

That erased incentives for manufacturers and government agencies to increase the supply of tests, according to senior administration officials and public health officials.

As the delta variant emerged and breakthrough cases started to rise in August and September, the views toward testing shifted again. But by that point valuable time had been lost.

“I think they were just trying to understand the implications and use their resources wisely,” said Andrew Sweet, managing director of covid-19 response and recovery at the Rockefeller Foundation. “That’s the hard thing about making policy during a pandemic — the science changes. You have to be able to change policy.”

Biden’s team disputes the idea that testing was ever de-emphasized. Tim Manning, the White House’s covid supply coordinator, said the administration worked initially to get reliable rapid tests authorized for emergency use, though that did not happen until the summer.

He said that the Biden administration used the Defense Production Act multiple times to secure raw materials and expand capacity, starting in February.

The strategy has been to try to get tests to schools, long-term-care facilities and vulnerable communities. “There’s widespread, free testing available all across the country,” Manning said. The new steps that Biden is taking represent “an expansion” on the work his team has already been doing to make over-the-counter rapid tests available.

He said the long wait many Americans are experiencing “indicates a high level of demand.” And he noted that other countries are also struggling with demand for tests amid the omicron surge.

“The volume of tests needed at any given time is going to be dependent on the progress of the disease,” Manning said. “If you went back into the summer, there was significantly lower demand for tests, which is what led many of the companies to not make those further investments until we worked with them to do so.”

The Biden administration, he said, has signed a year-long contract with six different testing manufacturers, designed to support the companies in case demand for tests diminishes.

Still, like others on the Biden team, he acknowledged the response has not been perfect. “There is not a day that I don’t think about other things that we could have done,” Manning said, when asked how he would have approached testing differently knowing what he knows now.

Health experts say the testing itself is just one part of a comprehensive strategy. Biden’s plans do not provide for Americans to report their results to a central database, which would make it easier to track outbreaks.

There also needs to be adequate support for workers who get positive tests and must self-isolate to avoid passing on the disease.

“It’s a symptom of the relatively smaller investment in the public health measures compared to medical interventions,” said Joshua Sharfstein, vice dean for public health at the Johns Hopkins Bloomberg School of Public Health, referring to the lack of testing. “It’s about whether people can get tests and then take action to protect themselves.”

A larger question for many health experts is whether the White House will see this moment as a time to return to the idea of a “wartime footing” — given that the country is seeing about 9,000 covid deaths a week.

“One can make a strong argument that we are at war, but for the White House to recommit to a wartime position, that’s really hard to do,” Kocher said. “It’s going to end in people saying, ‘Why didn’t you win the war the first time?’ It’s hard to go back. But biology is hard.”

Tyler Pager, Dan Diamond and Yasmeen Abutaleb contributed to this report.