Susan Walsh / AP
Defense Secretary James Mattis is warning our NATO allies to pay up on their treaty commitments by the end of the year, or the U.S. will "moderate its commitment," per the Associated Press.
The target number: 2% of gross domestic product.
Why it matters: Forcing our allies to pay more for their treaty obligations is a core part of Trump's foreign policy promises. Having Mattis deliver this message is a clear signal that it wasn't left with the campaign.