Turkey violated international law by converting the Byzantine-era cathedral into a mosque, the Greek Orthodox Archdiocese of America claims.
The president's threat to target cultural sites was in keeping with his longstanding disregard for international law.
Destroying cultural property during armed conflict is considered a war crime under international law, one the U.S. has decried in the past.
The Pentagon said Gen. Qassem Soleimani was “actively developing” plans to kill American diplomats, but the details of the plot remain unclear.
The secretary of state said the U.S. no longer considers the expansion of Israeli settlements in the West Bank to be a violation of international law.
A Chinese Embassy statement said "bullies" will "end up in the ash heap of history."
A State Department spokeswoman said it had been determined that Russia “has used chemical or biological weapons in violation of international law."
That leaves some of the current detainees stuck in a legal "no man's land," a federal judge said.
Trump's Supreme Court nominee spent years defending the government's right to imprison some people without charge.
Campaigners can use the moral force of international law to drastically reduce pollution to oceans.