Donald Trump's advisers offered him several options aimed at fulfilling his desire to pull back U.S. troops in Syria without allowing Turkey to commence its incursion. One tactic on the table: threatening to recognize the deaths of millions of Armenians and members of other ethnic minorities under the Ottoman Empire as a genocide, a National Security Council official told Newsweek.

Whether or not the deaths of up to a million and a half Armenians and hundreds of thousands of Greeks and Assyrians in 1915-1923 should be termed a "genocide" is a controversial topic in international relations. Turkey, the modern-day successor to the Ottoman Empire, rejects that these events constituted a systematic campaign to slaughter ethnic minorities, but more than 30 countries and governments have gone on the record to say it does.

Related: The Assyrian Genocide

The United States government has not joined them. While 49 U.S. states--Mississippi is the sole exception--have officially recognized the Armenian genocide, no federal legislation to do so has ever succeeded.

The issue has high-profile supporters. This past April, Senators Bob Menendez of New Jersey and Ted Cruz of Texas introduced a resolution "affirming U.S. recognition of Armenian genocide." Democratic presidential contenders Elizabeth Warren and Kamala Harris signed on, as did Rep. Tulsi Gabbard to the House version.