1. Congress allocates money to be spent. The President spends the allocated money.
2. Once Congress allocates money, their job is oversight of the money being spent. They don't spend the money and have no say HOW it gets spent as long as it's spent legally. That's their job to monitor with oversight.
3. Once the President is given the money with the instructions to spend it, he has a number of choices to make in spending it. There are some rules he has to follow & some of the money is fungible and some isn't.
4. However there are some other factors that are in play here. One of them is that 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.
5. This opens up new options.
6. By making these two declarations President Trump has just communicated that he has the authority to NOT spend any funds he doesn't deem necessary and will return them to the US Treasury. So, funds for Planned Parenthood? He can simply not allocate the funds.
7. Also, these declarations make some funds fungible. For instance 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.
8. Congress is powerless to stop cash reallocations on an omnibus bill AND cannot stop the DOD from taking measures under a declared Emergency.
9. Despite their language in the Omnibus Bill about the Border Wall, it is trumped by the State of Emergency that Trump declared.