The Math Behind Trump’s $1 Trillion Defense Budget

OPINION — “The President’s FY ‘26 [Fiscal Year 2026] National Defense Budget requests $1.01 trillion, which is a 13 percent increase from FY ’25 enacted [as authorized but not yet funded by Congress] levels. This [FY ‘26] includes $848.3 billion for DoD’s [Defense Department’s] discretionary budget and $113.3 billion in mandatory funding for DoD via [the FY ’25] reconciliation [bill now before the Senate] totaling $961.6 billion total for the Department of Defense.”

That was a Senior DoD Official briefing reporters last Thursday, on newly-released details of the Trump administration’s defense budget request for the fiscal year 2026, which begins October 1, 2025 and ends September 30, 2026.

In the best of times, the DoD budget process is difficult to understand, but this year it is even more complicated than most. The final defense budget figure depends not only on passage of the FY 2026 Appropriations Bill, but also on the FY 2025 reconciliations bill.

In addition, there are some interesting differences among the Pentagon, House and Senate on how the money is to be spent.

Ideally, a President sends his annual budget proposal to Congress early in the year—late January for example. Congress holds authorization hearings followed by appropriation hearings, and the bills get marked up and passed before the next federal government fiscal year begins on October 1.

But when it comes to defense, for 11 of the past 12 fiscal years, DoD has had to operate under continuing resolutions (CRs) for some months because Congress in those years was unable to pass the necessary defense appropriations bills until after the new fiscal year began.

From DoD’s point of view, that has caused problems because under CRs spending levels normally remain the same as the previous year. CRs also prohibit new starts, disrupt production schedules and generally interfere with defense planning. The situation becomes even more complicated in years of presidential transition.

The fiscal 2025 defense budget was originally put together under the Biden administration. Congress, after President Trump was elected, delayed passage of the Biden fiscal 2025 defense spending plan, approving two short-term CRs. Finally, after Trump became president, Congress approved a full year CR in mid-March 2025. That put DoD funding for this current fiscal year at $852 billion, just one percent above what it was in FY 2024.

Meanwhile, the Trump administration was working with DoD officials on the FY 2026 defense budget, which the Biden administration back in 2024, had projected would be $876.8 billion.

Then, on April 7, 2025, during a joint press conference with Israeli Prime Minister Benjamin Netanyahu, Trump, after mentioning that he had built up the U.S. military during his first term in office, suddenly said, “We have great things happening with our military.”

Trump went on to say something that he had not said publicly before: “We also essentially approved a budget…you’ll like to hear this, of a trillion dollars, $1 trillion and nobody’s seen anything like it. We have to build our military and we’re very cost conscious, but the military is something that we have to build and we have to be strong because you got a lot of bad forces out there now. So, we’re going to be approving a budget and I’m proud to say, actually the biggest one we’ve ever done for the military.”

Trump’s statement about $1 trillion for defense in FY 2026 then became the marching order, but how to do it was the question. A month later, the answer appeared publicly in the form of the FY 2025 reconciliation bill.

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Since the January presidential inauguration, the Trump administration and Republican leadership had been working on this reconciliation bill in order to change much of the Biden FY 2025 budgeting by aligning all spending, taxes, revenue, and the debt limit with a new, agreed-upon FY 2025 Trump budget.

Among many features of this FY 2025 Trump reconciliation bill was the insertion of a $150 billion lump sum for defense programs, to be paid out of U.S. Treasury funds available through 2029. There had been no congressional hearings—the number just appeared.

In early May, when Trump’s Office of Management and Budget (OMB) released its full government fiscal 2026 ‘skinny’ budget, public mention was first made of the $150 billion defense package in the reconciliation bill — and that some $113 billion of it was to be earmarked for the Pentagon’s fiscal 2026 budget.

That meant DoD’s FY 2026 base budget remained near FY 2025’s $852 billion, but you reached Trump’s announced $1 trillion for overall defense spending by adding the $113 billion in the reconciliation bill along with funds for nuclear weapons paid for by the Energy Department.

Back in May, at the time of that OMB announcement, Senate Armed Services Committee Chair Roger Wicker (R-Miss.) said, “For the defense budget, OMB has requested a fifth year straight of Biden administration funding, leaving military spending flat, which is a cut in real terms…I have said for months that reconciliation Defense spending does not replace the need for real growth in the military’s base budget.”

He was joined at that time by Sen. Mitch McConnell (R-Ky), the chairman of the Senate Appropriations Defense Subcommittee, who said, “Make no mistake: a one-time influx reconciliation spending is not a substitute for full-year appropriations.”

On May 22, in a 215-to-214, largely party-line vote, the House passed its version of the FY 2025 reconciliation bill, containing the $150 billion defense package. The reconciliation bill is now up for debate in the Senate. An advantage for the Trump administration in the reconciliation process is that Senate rules allow for a simple majority vote (51 votes) for reconciliation bills, bypassing the usual 60-vote threshold on controversial measures needed to overcome a filibuster.

Meanwhile, House and Senate Armed Services and Appropriations Committees have held hearings on the Trump fiscal 2026 DoD budget request with mixed results.

On June 12, the House Appropriations Committee passed its version of the FY 2026 DoD funding bill that followed the OMB May proposal, keeping the numbers close to the FY 2025 level and reaching the $1 billion Trump goal by adding the earmarked $113 billion in the pending FY 2025 reconciliation bill.

However, questions were raised at the June 18 Senate Armed Services Committee hearing in which Defense Secretary Pete Hegseth was one of the witnesses.

Chairman Wicker said, “What we have in front of us is an inadequate budget request with precious little detail and no follow on data about fiscal years 2027, 2028, or 2029. We must assume, and in fact we have heard, that OMB intends to maintain defense spending at $893 billion across the four years of this administration. So even with a one-time $150 billion [fiscal 2025] reconciliation [bill] infusion, this would leave us at 2.65% of GDP by 2029, below 3 percent of GDP and well below the 5 percent of GDP that we really need.”

Wicker went on, “I understand that if you put reconciliation and the budget request together for this year [FY2026] it exceeds 3 percent, but if we go back to that same baseline for the next three years, after that we’ll be under 3 percent. Do you intend to fix that?”

Hegseth agreed that going below 3 percent would be very dangerous, adding, “So does the President of the United States which is why this budget increases from FY25 1.3 percent [if you include reconciliation bill’s $113 billion] and puts us at 3.5 percent of GDP on defense.”

President Trump recently returned from the NATO summit at The Hague where he took credit for the allies adopting a 2035 goal of 3.5 percent for member countries’ core defense spending. It could be embarrassing for the President to find himself below that amount back home.

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Another question raised at Wednesday’s Armed Services hearing was exactly how the reconciliation bill defense money would be spent. At issue was the tradition known as “congressional intent,” for Congress to designate spending amounts for specific defense items in legislation.

At the June 18 Armed Services hearing, Wicker asked, “We will put funds in the reconciliation bill, working with the House and working with the Administration, to get the [President’s] signature on the bill. And we will make clear alongside that the specific congressional intent [on defense items]…Mr. Secretary [Hegseth] do you commit to following congressional intent unequivocally on reconciliation.”

After Hegseth gave a qualifying answer, Wicker demanded, “Do you commit to following congressional intent unequivocally in reconciliation?” This time, Hegseth answered, “Yes.”

I mention this because last Wednesday, Chairman Wicker released what he called an “updated legislative text of the defense reconciliation bill.” It showed his committee had cut down to $1 billion the $3.3 billion it had previously allocated to deployment of military personnel in support of border operations.

However, the next day, Thursday, at a Pentagon press conference called to discuss the FY 2026 defense budget, details of which had just been made available, a Senior Defense Official made clear the figure DoD had for the reconciliation bill was different. He said, “The $5 billion we’re requesting [from the reconciliation bill] is for border security for our troops to actually be there as well as for detention support.”

The Defense Official added of the reconciliation funding, “It’s the first time the Department of Defense has received mandatory money like this. It’s ten-year money with a lot more flexibility than the average discretionary dollar provides.” Remember, under traditional circumstances, congressional intent language in statutes determines how defense money is to be spent.

Under the original reconciliation bill, DoD had 90 days after the legislation became law to send the House and Senate Armed Services and Appropriations Committees their plans for spending the $150 billion. What was to happen thereafter is not spelled out, but it’s clear the “flexibility” that the Defense Official has seen is not recognized by Sen. Wicker and, I expect, others on Capitol Hill.

Will today’s complex circumstances be repeated?

I saw a hint in something the Senior Defense Official said to reporters last Thursday. Asked about the top defense budget figure for FY 2027, he said, “We have not yet discussed what that will look like for [FY] ’27. But unless the president’s tone changes, I imagine we’ll stick with $1 trillion for national defense spending.”

After the June 18, Armed Services hearing, Sen. Angus King (I-Maine) said, “As I understand it, OMB is saying we are going to have a flat defense budget for the next four or five years. Are we playing reconciliation every year from now on?”

The answer is maybe.

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