President Trump promised to be a great dealmaker.

Unless he's a sadomasochist, however, his spending deal isn't great. After all, the deal — likely to be approved this week — is loaded with Democratic Party spending priorities. Republican spending cuts have been surrendered. Instead, the federal tap will flow new debt-laden cash into bankrupt Puerto Rico and various government agencies. It's a steep price for the two GOP priorities that survived: small increases in defense spending and border security.

Recognizing the optics of his failure, Trump took to Twitter.

"Our country", he said, "needs a good shutdown in September to fix mess."

It's a necessary threat.

Republicans must use the Sept. 30 deadline (when this spending resolution is set to end) to negotiate serious spending cuts. If they fail, Democrats will hold the initiative until next year's midterm elections. That's because, absent a credible Trump policy agenda, GOP members of Congress will see Trump as a weak leader. They will be unwilling to put their offices on the line to serve his gambits. Trump must address this trust deficit. A good start would be getting an Obamacare replacement into law. Trump needs a quick victory beyond now-Justice Neil Gorsuch's Supreme Court confirmation. Put simply, he must show he can win.

Next, Trump needs a three-pronged strategy to use the threat of a government shutdown to his benefit.

1. Trump must unite Republicans by putting his credibility on the line

To win future victories, Trump must first accept responsibility for past failures. Like President Harry Truman, Trump needs to recognize that the buck stops at his desk. As Susan Ferrechio reports, conservative Republicans are losing patience with Trump's dithering. But Trump can't rely on conservatives alone. If he does, Republicans from toss-up districts and states will face pressure to back down and break the shutdown. To consolidate those Republicans, Trump must become the political equivalent of William the Conqueror at the 1066 Battle of Hastings. Instead of sending Steve Bannon to threaten members of Congress, Trump must lead from the front and stake his presidency on victory.

Again, it is impossible to understate the importance of personal leadership here. Trump won the presidency by convincing enough Americans that he gets results. If Americans, and members of Congress, see that same personality come September, they will be far more likely to support Trump's corner. Trump needs to get out of the White House and help Speaker of the House Paul Ryan and Senate Majority Leader Mitch McConnell bring Republicans together.

2. Trump must prioritize long-term spending reductions

Trump's existing budget focus is obsessed with discretionary spending cuts. But while those cuts should be part of Trump's budgetary agenda, they are alone insufficient. Federal government spending is approaching 21 percent of GDP. A reduction to between 18-19 percent is both possible and preferable.

But Trump cannot ignore the core drivers of the deficit: entitlements and defense spending. We need a strong military that can deter and defeat our global adversaries. That means significant spending. But it also means efficient spending on effective capabilities. The Pentagon currently wastes far too much money on inefficient procurement programs. Trump should build on his F-35 success and find new efficiencies. For one, as the Congressional Budget Office notes, the Navy's 355-vessel fleet plan is very expensive.

Medicare and Social Security reforms are also key. While some conservatives such as Pat Buchanan disagree with reform here, the math is undeniable. As the CBO shows, under current law, the national debt will reach 106 percent of GDP by 2035 and 150 percent by 2047. Combined with increased net-interest payments on the debt, America's future generations face a dark future. Sadly, though, there are many possible solutions (here are mine), but Trump has thus far pledged to ignore entitlements. It's time for him to change course.

3. Trump must reach across the aisle

To get 60 Senate votes come September, Trump will need the support of eight Democrats. It's a tough ask. But not an impossible one. Preparing for the showdown, Trump needs to build relationships with moderate or flexible Democrats. The following senators offer that opportunity: Sens. Cory Booker, Heidi Heitkamp, Joe Manchin, Patty Murray, Bill Nelson, Mark Pryor, Jon Tester, and Mark Warner. Yes, Trump will have to offer concessions to attract Democratic support. But a good deal can be reached and a government shutdown avoided.

Ultimately, Trump must realize he is the one who has most to lose from this crisis. If he backs down come September or fails to offer serious spending plans, the president's credibility will suffer immense damage. Alternatively, offering compromise alongside resolute leadership, Trump can get a good deal.

As Trump noted during the campaign, Americans want action. It's time to deliver.

Tom Rogan (@TomRtweets) is a contributor to the Washington Examiner's Beltway Confidential blog. He is a foreign policy columnist for National Review, a domestic policy columnist for Opportunity Lives, a former panelist on The McLaughlin Group and a senior fellow at the Steamboat Institute.

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