In January 2019, the Democrats under Nancy Pelosi's wonderful leadership, take control of the House of Representatives where all Spending Bills must originate.
As you might recall, the Democrats hate Defense Spending as every dollar they can divert from the Defense Budget can be poured into their never ending quest to buy votes by giving money away in Social Programs.
Then in Two Years time we have another Presidential Election, an election that will put every single House Seat up for grabs again, and large number of Senate Seats..
When it comes to Defense spending .....nothing is etched in stone because of the way in which the fingers on the Cash Register Keys are affected by Election outcomes.
Trump ran on rebuilding the US Military and had the benefit of Republican control of both Houses of Congress upon taking office.
Any Spending Bill will have to start in the House....go to the Senate for its mark ups....then to a Conference where both Houses seek some workable compromise.
Don't hold your breath thinking you will see a large fleet of new F-15's ever.....as the Teeter-Totter is now leaning back towards Social Spending rather than Defense Spending.