Donald Trump is entering the second year of his presidency, but he and Republicans in Congress will need to govern as though it’s his last.

After months of inaction on the top items in their shared legislative agenda, they closed out 2017 with a bang. A tax reform bill that also repealed Obamacare’s individual mandate and allowed drilling in the Arctic National Wildlife Refuge became law in December, capping a busy year of deregulation, military gains against the Islamic State, and successful conservative judicial nominees.