Seventeen “flag-rank” officers who wrote to former President Obama expressing their concerns on his decision to allow transgender individuals to serve in the U.S. military have now sent a letter of thanks to President Donald Trump for his decision to reverse the policy.

“We write today to express our gratitude to you for making the extremely courageous decision to reverse President Obama’s transgender social experiment,” the letter, sent last week, said.

“There may be an enormous amount of vitriol directed at you for making this policy correction, but please know that overturning this policy may have done more in the long-term to save the culture and war-fighting capacity of the U.S. military than perhaps any other military policy you will adopt as president,” the letter said.

“It’s just not compatible with the mission of the military,” Paul E. Vallely, one of the 17 military members who signed the letter, told Breitbart News.

Vallely said this kind of “social engineering” conflicts with the military’s need to be “ready to go to battle to protect America.”

The letter cited an estimate by the Family Research Council — which spearheaded the letter effort — that said that, aside from the affect on military readiness, the transgender inclusion policy would cost between $1.9 and $3.7 billion in special compensation for services such as gender-transition surgery and other treatments.

Lieutenant General William “Jerry” Boykin (Ret.), who is also executive vice president at FRC, posted on his Facebook page a lengthy expression of support for Trump’s decision that says, in part:

“To say that I am pleased to see #PresidentTrump put a stop to this #transgender madness in the #military would be an understatement,” Boykin wrote. “It is another indicator to me that our new #President is truly focused on #militaryreadiness.

“The transgender policy as designed contributed nothing to that readiness,” Boykin said.

“In closing Mr. President, we note that your bold decision is supported by the American people who have a great reverence for the military,” the letter concluded. “A Rasmussen survey released in June found that ‘just 23% of likely U.S. voters think the U.S. military’s decision to allow openly transgender people to serve is good for the military.’”

“Once again, thank you for your focus on preserving the military effectiveness, morale, and social cohesion of the United States Armed Forces,” the letter concluded.

One of Trump’s tweets announcing the transgender policy on July 26 got 142,000 likes.

….victory and cannot be burdened with the tremendous medical costs and disruption that transgender in the military would entail. Thank you — Donald J. Trump (@realDonaldTrump) July 26, 2017

“Victory and cannot be burdened with the tremendous medical costs and disruption that transgender in the military would entail,” Trump tweeted. “Thank you.”

In addition to the letter, FRC launched a petition campaign and the American Family Association also sought petition signatures in support of Trump’s policy. The petitions combined have collected more than 60,000 signatures.