President-elect Donald Trump has a problem. It’s not one unique to him. It’s something every second-term president faces, regardless of when the term takes place.

Although presidents are elected to four-year terms, in reality, they operate in two-year increments. The Republican or Democrat rides to victory in November, often but not always, carrying his party with him to majorities in Congress. The new government has the power to make good on the promises everyone made on the campaign trail. The minority party is left with the unenviable job of trying to thwart the majority.