Last March, Defense Secretary Jim Mattis told the military to stop being so publicly honest about the things it cannot do.

Multiple stories about ground units that could not deploy, aircraft that could not fly, ships that were wearing out didn’t help. That type of public transparency no longer was encouraged. Whatever the reality was behind closed doors, the public message from then on, Mattis encouraged, was to be one of strength.

But this has created problems for top military leaders as they prepare to testify before Congress to ask for more money.

Mattis never provided specific rules on what military leaders can and cannot say.

“I wanted to pass along some guidance from Secretary Mattis. He wants us to be cautious about publicly telegraphing readiness shortfalls,” then-Office of the Secretary of Defense director of press operations Navy Capt. Jeff Davis told the military’s senior public affairs officials in a memo obtained by Military Times.

“While it can be tempting during budget season to publicly highlight readiness problems, we have to remember that our adversaries watch the news too. Communicating that we are broken or not ready to fight invites miscalculation.”

It was “message received” for military officials, who quickly re-evaluated what they were saying in testimony, what media engagements were occurring and how to communicate moving forward.

The difference in transparency has been felt on Capitol Hill too ― by the very lawmakers who will be responsible for convincing members not serving on an armed services committee that the military’s aircraft, ships and ground forces need more money.

“Some of the folks in DoD are reluctant to talk too openly about our shortfalls because you’re broadcasting that to your potential adversaries,” House Armed Services Committee Chairman Rep. Mac Thornberry, R-Texas, said Thursday. “And I admit, it’s a fine balance. But if we’re going to convince my colleagues who are not on this committee, as well as the American people, to fix these things, I think we do have to at least talk somewhat openly about what our problems are.”

On Thursday, Pentagon Press Secretary Dana White said the services had not received direction to keep quiet on readiness shortfalls.

“There’s been no direction to not talk about readiness issues,” White said at a press briefing. “The secretary wants his commanders to talk about readiness.”

White said sometimes there would be the need to discuss readiness challenges with Congress in closed sessions, but that military leaders would keep communicating the state of the military’s readiness.

“The American people need to know that we are ready to go tonight,” White said.

In the 2017 guidance, Mattis urged the forces to continue to engage with the press — but corral the message provided.

“This does not mean we should stop bringing press to our bases, ships, aircraft, units, etc.,” the guidance said. “But we must always project strength when we do it. You will see similar guidance passed via Leg Affairs channels for how readiness is discussed in testimony. As much as possible, [Mattis] wants to move this out of the public domain and into private meetings or closed hearings.”

The caution came after Mattis saw media reports in early spring 2017 that concerned him, two defense officials said who spoke on condition of anonymity. Mattis thought the stories had enough details about the challenges faced by ground units that were not ready to deploy and aircraft that could not fly as to broadcast U.S. vulnerabilities to potential adversaries.

In his most recent talk with reporters, Mattis said that readiness has improved in his first year as defense secretary — but provided no statistics to support the assertion.

“Readiness is upping as we speak,” Mattis said. “I don’t announce all that, because I see no need to tell the enemy in advance where we’re at in certain areas. But we’ll continue what we’ve been doing. It is very specifically ... from ... things we’re doing with the numbers of troops and Army brigades to the specific munitions that we’re working to max out the production capabilities. All that stays on track.”

One defense official who spoke on condition of anonymity said the directive was not meant to be a gag order but a way to stop what has been viewed as a growing tendency by military leaders testifying before Congress to emphasize how bad off their forces were, the official said.

As the services prepare for televised 2018 budget testimonies, there have been questions on what they can actually say, multiple officials said.

The services still face significant challenges in being able to generate the forces needed for future conflicts. The language military leaders are choosing to use has become more blanket, less transparent and harder to evaluate whether the state of the military’s readiness is improving or further eroding.

For example, in a request to the Army on aircraft inventory, only ranges of numbers were provided, and no information on the number of those aircraft that are currently able to fly — a piece of data reporters have regularly obtained for years as a way to track the health of the force.

In the Navy, the two fatal collisions in the Pacific last year forced it to remain more transparent through Congressionally mandated reviews such as the comprehensive review it undertook of the state of its fleet following the fatal accidents, a Navy official said. In recent public statements, officials have been more general in what they say the Navy still needs.

At the Surface Navy Association’s annual conference this week, Vice Adm. Thomas Rowden, commander of Naval Surface Forces, said the western Pacific’s 7th Fleet needs “time to maintain their gear, time to refresh their basic individual and team skills, and time to unwind.”

He added, “Time will only come from one of two things, or a combination of them. More ships, and fewer obligations. It is hard to see things any other way.”