President Donald Trump’s stated reason for renewing the ban on transgender military service doesn’t just represent a step back for LGBTQ equality — it also has absolutely no evidence behind it.

Trump tweeted on Wednesday that he would ban trans military service because “[o]ur military must be focused on decisive and overwhelming … victory and cannot be burdened with the tremendous medical costs and disruption that transgender in the military would entail.”

Yet before the Obama administration moved to lift the ban on transgender military service last year, the issue had been studied. On both the military readiness and cost fronts, the findings are clear: Allowing trans people to serve would not be disruptive, nor would it entail tremendous medical costs.

Allowing transgender people to serve openly has “little to no impact” on military readiness

A 2016 study from the RAND Corporation summarized the evidence. It pointed out that 18 other countries — including Australia, Canada, Israel, and the United Kingdom — allow transgender people to serve openly in the military with “little or no impact on unit cohesion, operational effectiveness, or readiness.”

The main reason: Trans people simply aren’t that large of a population. Based on RAND’s estimates, trans troops make up around 2,450 of the 1.3 million active-component service members — a fraction of a percent of the US military. While some trans service members would seek treatment, RAND pointed out that only a small subset would: “Estimates derived from survey data and private health insurance claims data indicate that, each year, between 29 and 129 service members in the active component will seek transition-related care that could disrupt their ability to deploy.”

RAND concluded this will have a very tiny effect, if any, on military readiness, finding that “the readiness impact of transition-related treatment would lead to a loss of less than 0.0015 percent of total available labor-years in the active component.” In comparison, “in the Army alone, approximately 50,000 active-component personnel were ineligible to deploy in 2015 for various legal, medical, or administrative reasons — a number amounting to around 14 percent of the active component.”

Trans medical care would only be a very tiny cost for the military

For this same reason, the costs of trans people seeking gender-affirming treatment would be fairly small. RAND found: “Using private health insurance claims data to estimate the cost of extending gender transition–related health care coverage to transgender personnel indicated that active-component health care costs would increase by between $2.4 million and $8.4 million annually, representing a 0.04- to 0.13-percent increase in active-component health care expenditures.”

This reflects the experience of other government bodies that have adopted trans-inclusive policies. For example, when San Francisco began to offer trans-inclusive health coverage to its employees in 2001, the city applied a small surcharge to all employees enrolled in its health plan. But the city ended up using just $386,000 of the $5.6 million raised by the policy — a cost so low that it eventually dropped the additional charge altogether.

“[D]espite actuarial fears of over-utilization and a potentially expensive benefit,” San Francisco’s Human Rights Commission noted, “the Transgender Health Benefit Program has proven to be appropriately accessed and undeniably more affordable than other, often routinely covered, procedures.”

Allowing trans people to serve openly, then, would not only be the right thing to do for equality and inclusiveness, but it would very slightly boost the pool of eligible recruits — all with little to no cost to the military’s readiness and budget.

The real reason for the change seems to be political

So why would Trump do this? The real reason, it seems, is politics. One administration official told Jonathan Swan at Axios: “This forces Democrats in Rust Belt states like Ohio, Michigan, and Wisconsin, to take complete ownership of this issue. How will the blue collar voters in these states respond when senators up for re-election in 2018 like Debbie Stabenow are forced to make their opposition to this a key plank of their campaigns?”

In other words, Trump, who once said that he will protect “L, G, B, T … Q” people and held up a Pride flag at a campaign event, has turned trans people — in the military, no less — into a political pawn.