Originally Posted by Acepimp

Normally that would be true. However, the President has declared a Human Rights Emergency AND has notified Congress that he's invoking the Balanced Budget and Emergency Deficit Control Act of 1985. By making these two declarations President Trump has communicated that he has the authority to NOT spend any funds he doesn't deem necessary and will return them to the US Treasury.

If he determines that building a Wall on the Southern Border is a defense against Human Trafficking, he can move funds from anywhere else in the Defense Dept Allocation & simply build the Wall. Congress is powerless to stop cash reallocations on an omnibus bill AND cannot stop the DOD from taking measures under a declared Emergency. Despite their language in the Omnibus Bill about the Border Wall, it is trumped by the State of Emergency that Trump declared.

This article is from March, 2018:

President Trump hints he may use Defense budget to build the border wall now