President Trump recognizes that Congress spends too much money on wasteful programs and not enough on border security. Yet he can’t seem to extend his Twitter opposition to their proposals to a full-fledged veto threat. By agreeing to sign every swampy budget bill, including even supplemental spending with no clear “must pass” deadline, he is giving away any leverage he might ever have to enact his priorities, not just until 2020, but even for the four years thereafter of potential Republican trifecta control of government.

Headed into this week, Democrats demanded $19 billion in more spending, including another Puerto Rico bailout, with no funding for the biggest crisis of all – the border. President Trump vigorously criticized the Puerto Rico bailout. His own budget calls for much lower spending levels, and he demanded $4.3 billion in border funding. So Republican leaders, led by Sen. Richard Shelby, R-Ala., did what they typically do, which is “split the difference” and “compromise” … by giving Democrats everything they want on wasteful programs and allocating nothing on border security. They wagered that Trump’s opposition would soften the minute they agree to pass the bill. They were right. Rather than vetoing the bill, the president promised to sign it.

Just eight Senate Republicans opposed the bill on Thursday. Today it is headed back to the House, where Democrats are trying to pass it without a recorded vote. (Update: Rep. Chip Roy, R-Texas, refused unanimous consent in the House, forcing a recorded vote and delaying the bill until after Congress returns from the holiday recess.)

The excuses are always the same. For the first two years, it was the 60-vote threshold in the Senate. Now it’s the Pelosi-controlled House. For the second term it will be the 60-vote threshold in the Senate again. But everyone is missing the point. The president’s ironclad commitment to backing his initial opposition with an irrevocable veto threat will change the arc of debate over these bills and give him leverage to at least secure some of his priorities, even as we spend ourselves into oblivion.

God forbid should we ever oppose a new disaster spending bill after $117.5 billion of disaster spending on top of record base spending for all the agencies receiving money in this bill, including those the president promised to eliminate altogether. Forget about standing behind the promise of no more money for Puerto Rico until the province makes systemic reforms. The president could at least have stood by his demand that if Democrats want more spending for their pet HUD projects under the guise of a disaster, then we need spending for the biggest disaster of all at the border. Trump’s request didn’t even include wall money.

This comes a day after the Republican-controlled Senate Armed Services Committee, led by Sen. James Inhofe, rebuffed the president’s request for $3.6 billion in border infrastructure funding in military construction accounts. Amidst the endless spending for social work in Afghanistan, Iraq, Syria, Niger, Libya, and Somalia, there is nothing for what is quintessentially national defense. But that is all because the president is scared of the four-letter word – VETO.

It’s hard to imagine when Trump will find greater leverage and a more auspicious opportunity again. The reality is that even with Republicans in charge of the House, every single budget legislation that passed in 2017-2018 was a Democrat bill without the proper border security priorities. That is because Republicans knew that if they passed the bill, the president would never veto it. They were right. That same pattern will hold, even in the best-case scenario of the outcome in 2020, unless the president steps up his veto game.

But this case was even worse. When it comes to full government funding bills or debt ceiling increases, the president has already been convinced that no matter the strength of his arguments, he must give the bipartisan congressional swamp whatever it wants for fear of the dreaded government shutdown or so-called default on the debt. But in this case, while both parties set an arbitrary deadline to pass it before Memorial Day, there was nothing special about that deadline. There would be no shutdown of any sort.

The president could easily have leveraged the holiday weekend to give speech after speech on how our Border Patrol has essentially been shut down permanently and on how this spending bill must reopen the most vital aspects of our national defense. He could have used the time to hammer home the cascading effects of illegal immigration and cartel control of the border on the security of this country.

Trump could have further buttressed his leverage by declaring a complete shutoff of asylum at the border, using his inherent executive authority to deny entry and his delegated authority under immigration law. He could have threatened to end DACA using the Administrative Procedure Act. Indeed, the veto pen, backed by the bully pulpit and existing executive authority, is quite a potent tool. But he gave in without a fight, even though there was no pressure of a shutdown.

On June 4, 1787, during the debate over the structure of the president’s check on Congress, James Wilson predicted that the veto would be so powerful that it would “seldom” be used. Indeed, this was not because of the weakness of the veto but because he thought Congress “would know that such a power existed, and would refrain from such laws, as it would be sure to defeat.” Imagine if Senate Republican leaders knew that all their mischief is destined for certain defeat? Sadly, they know now that their bad spending bills and disregard for the border are destined for certain success the minute they are proposed.