What DACA and ACA insurance company subsidies have in common...

At first glance, the answer to this question seems to be pretty much nothing. But at closer inspection, the answer (from a technical aspect) is fairly obvious, and fairly important. Of course I am betting that most people do not hear much about what they have in common. Rather your pundits and politicians will argue ad nauseam about the merits of the two issues, without a care in the world about the underlying constitutional facts. But here they are:

• Neither DACA or the ACA insurance company subsidies are a matter of law, but rather policies enacted outside of Congressional action. DACA was purely an executive order, and not one that was meant to clarify any existing law. The ACA insurance company subsidies were only provided (according to the law) as a temporary thing, to help with start up costs. But President Obama and his administration continued to pay these subsidies to insurers (after the subsidies effectively ended) with money that was legally appropriated elsewhere.  
• Both DACA and the ACA insurance subsidies have been challenged in court.. While there has been no rulings on DACA (ten states have sued), the similar program DAFA was struck down at the fifth court of appeals. Meanwhile, the ACA insurance company subsidies were also declared by the courts to be illegal, although the judge agreed to let them continue while the case made it's way through the appeals process. That appeal, however, could be dropped by the current Justice Department, effectively leaving the original court case in place, and making those payments illegal.  Correction: Courts have concluded that State Attorney Generals can defend the payments in court - but I think it would be legally daunting to believe a court would order that the President "must" use funds not legally allocated to continue payments. 

So if you add this up... both of these issues involve what many believe to be a overreach of Presidential power by the previous Administration. To some degree there is a very reasonable argument that both actions were (and will eventually be ruled by the courts to be) outside of the jurisdiction of the office of the President.

Moreover, because neither is a matter of actual law, it really is as simple as the next President deciding not to follow the same path. If not Trump, then any one of the future Presidents we might elect would have the same authority to undo these policies. Both DACA and the subsidies to insurance companies would "always" be at the mercy of the office of the Presidency, and could always be undone with the stroke of a pen.

By overturning DACA, and ending the subsidies... President Trump would only be ending the Obama overreach. Both issues should (by all legal means) come under the constitutional authority of Congress. If Congress wants to write a law that replaces DACA, then they should go ahead and do it. If Congress wants to allocate funding for subsidies to insurance companies, then they can write a law that appropriates that funding.

If they do not want to do it, or cannot come up with the means to accomplish it... then guess what: that's on Congress, not on the President. Contrary to popular believe there is no constitutional authority for the President to unsurp Congress with a phone and a pen... just because Congress doesn't do the President's bidding.

Would anyone arguing differently, really approve of Trump using funds appropriated elsewhere to start building his wall?