Trump is starting to draw battle lines with Congress on an issue with huge implications for the global economy

By sometime later this summer, Congress will have to raise the nation's debt ceiling. Both Congress and the Trump administration are starting to firm up their positions. Failing to raise the ceiling could lead to catastrophic effects on the economy. The deadline that led to the night President Barack Obama once called the "scariest moment" of his presidency is once again on the horizon in Washington. Raising the debt ceiling: At its core,a seemingly simple functionof Congress. Butthe battle over...