In a memorandum released Aug. 9, 2021, the secretary of defense explained how he will ensure the continued health and safety of the U.S military through the use of the available COVID-19 vaccines.

"I will seek the President's approval to make the vaccines mandatory no later than mid-September, or immediately upon the U.S. Food and Drug Administration licensure, whichever comes first," said Secretary of Defense Lloyd J. Austin III.

Right now, there are three COVID-19 vaccines available. All are currently being used across the United States under "emergency use authorization," or EUA, from the Food and Drug Administration.

Those vaccines include the ones from Pfizer and Moderna, both of which require two injections. The Johnson & Johnson vaccine requires only a single shot.

If any of the three vaccines receive full licensure by the FDA before mid-September, Austin said, they will become mandatory immediately. If they do not receive the licensure by mid-September, however, the secretary will request a waiver from the president to make them mandatory.

For service members who have religious objections to receiving a vaccine, the path for how they might seek an exception to the vaccine is defined by their individual military service's regulations, Pentagon Press Secretary John F. Kirby said during a meeting with the media on Aug. 10, 2021.

"There is a religious exemption possibility for any mandatory vaccine, and there's a process that we go through to counsel the individual both from a medical and from a command perspective about using a religious exemption," Kirby said.

Counseling, he said, includes a discussion with both a medical professional and a commander about the risks of not being vaccinated as well as how not being vaccinated might affect deployability, assignments or travel. Requests for religious exemption differ by service, he said.

"We take freedom of religion and worship seriously, in the military, it's one of the things that we sign up to defend," he said. "And so it's something that's done very carefully."

There are exemptions for mandatory vaccines for medical reasons as well, Kirby said, including pre-existing medical conditions.

"The primary care physician will be able to help make that determination," he said.

Nevertheless, the defense secretary and the department are confident that once the vaccines are mandatory, service members will do their part.

"We have every expectation that once the vaccines are made mandatory, the troops are going to ... do the right thing," he said. "Going forward with this particular vaccine, the secretary's expectation is that commanders are going to treat the administration of that vaccine with — as he wrote in his memo — professionalism, skill and compassion."

Kirby also said the department will ensure that every individual with reservations about getting a vaccine gets proper counseling on its safety and efficacy as well as how not getting the vaccine could affect teammates, readiness and the mission.