The massive spending deal, negotiated by Treasury Secretary Steve Mnuchin and House Speaker Nancy Pelosi and agreed to by the president, looks poised to kill off the Budget Control Act of 2011—the law that was meant to restrain federal spending. With that law on the way out, the question arises: Where can fiscal conservatives turn to exert real and lasting fiscal discipline? Thankfully, two members of Congress have introduced a bill to do just that. The Maximizing America’s Prosperity Act—or MAP Act—is a bill proposed by Rep. Kevin Brady, R-Texas, and Sen. Mike Braun, R-Ind., that would limit federal spending...