U.S. lawmakers have increasingly used the debt ceiling to re-litigate congressional spending, risking default and sparking debate over whether to abolish the ceiling.

President Trump has made reducing the U.S. trade deficit a priority, blaming trade deals like NAFTA, but economists disagree over how policymakers should respond.

Tariffs have been applied over the years to protect homegrown industries and target competitors who are seen as using unfair trade practices. They impose costs on both importers and exporters and had been in decline until the recent U.S.-China trade war.

President Donald Trump’s rejection of the Trans-Pacific Partnership (TPP) has intensified debate over U.S. trade policy and its far-reaching effects.