US President Donald Trump has expressed frustration at the time it's taking America's Food and Drug Administration to issue an emergency use authorisation for the coronavirus vaccine developed by Pfizer.
Last night, after a day-long hearing, an FDA advisory committee voted to recommend the vaccine's approval.
FDA Commissioner Stephen Hahn released a statement promising the organisation would move "rapidly" to finalise an official authorisation.
It hasn't been rapid enough to satisfy Trump.
The president went after Hahn on Twitter today, calling the FDA a "big, old, slow turtle" and ordering its head to "get the dam [sic] vaccines out now".
"Stop playing games and start saving lives!!!" he said.
A few hours later, The Washington Post reported Trump's White House chief of staff, Mark Meadows, had told Hahn to submit his resignation if the agency failed to issue the authorisation by the end of the day.
The Post says Meadows' warning prompted the FDA to move forward its timetable from Saturday morning (US time) to sometime on Friday.
Hahn denied the newspaper's reporting, calling it "an untrue representation" of his phone call with Meadows.
"The FDA was encouraged to continue working expeditiously on Pfizer-BioNTech's EUA request," he said.
"FDA is committed to issuing this authorisation quickly."
The vaccine in question has proved to be 95 per cent effective in clinical trials. Some other countries, including the United Kingdom and Canada, have already authorised its use.
It is hoped tens of millions of doses will be distributed to America's frontline health care workers and vulnerable populations before the end of December.
However, any vaccine won't be available to the broader American public for months. And that intervening period is going to be especially dangerous, as new infections, deaths and hospitalisations are rising across most of the country.
This week Dr Robert Redfield, head of the Centres for Disease Control and Prevention (CDC), warned the virus would kill more people each day in the coming months than died in the 9/11 terror attacks.
"We are in the time frame now that, probably for the next 60 to 90 days, we're going to have more deaths per day than we had at 9/11 or we had at Pearl Harbour," Redfield told an event hosted by the Council on Foreign Relations.
"The reality is the vaccine approval this week's not going to really impact that, I think, to any degree for the next 60 days."
The terror attacks on September 11, 2001 killed 2977 people. Japan's surprise strike on Pearl Harbour in 1941 killed 2403, and prompted America's entry into World War II.
If the US averages 3000 deaths per day for the next two months, that would mean another 180,000 dead by mid-February. Extend it to three months and that would be about 270,000 deaths by mid-March.
That last number would nearly double the country's current death toll of 292,000, which is already the worst in the world by far.
According to the Covid Tracking Project, the US is averaging 205,000 new cases each day and 2300 deaths.
Both numbers continue to rise sharply. It has exceeded 3000 deaths on each of the past two days. Meanwhile, 107,000 Americans are hospitalised.
These figures are all the highest they have ever been, and are worse than they were at the respective peaks of the country's first two waves.
For example, daily infections only reached a high of 35,000 during the first wave in April.
Covid Exit Strategy, which tracks the situation in each of America's 50 states, reports 49 are suffering from "uncontrolled" spread of the virus. The one exception is Hawaii.
Trump has remained focused on making vaccines from both Pfizer and Moderna available to the public, rather than trying to contain any further spread of the virus.
The president took a break from tweeting about his election defeat on Tuesday to hold an event highlighting Operation Warp Speed, his administration's programme designed to accelerate the development and distribution of Covid vaccines.
That programme has been a success so far. It enabled companies like Pfizer to invest heavily in development, knowing there would be a guaranteed pay-off afterwards if they were able to create an effective vaccine.
Trump spent most of his statement at Tuesday's event praising the speed at which the vaccines had been developed.
"We're here to discuss a monumental national achievement. From the instant the coronavirus invaded our shores, we raced into action to develop a safe and effective vaccine at breakneck speed," he said.
"We were able to get things done at a level that nobody has ever seen before. The gold standard vaccine has been done in less than nine months.
"We think by spring, we're going to be in a position that nobody would have believed possible just a few months ago. Amazing, really amazing. They say it's somewhat of a miracle, and I think it's true.
"When America is faced with a challenge, we come through, and we always come through to overcome every hardship and surmount every obstacle. And I think you'll be seeing that over the next few months. The numbers should skyrocket downward."