President Donald Trump's retreat from northeastern Syria has proven disastrous for the US's Kurdish allies in the region and shaken global faith in the US's credibility. The decision has opened the door to the resurgence of ISIS, it handed Russia a major geopolitical victory, and it's catalyzed a humanitarian crisis in Syria.
On the domestic front, Trump's decision prompted a swift, bipartisan rebuke in both chambers of Congress, including from top Republicans.
Trump's move has had virtually no political or strategic benefits, which begs the question: was the president motivated by something other than the US's national interests when he pulled troops from northeastern Syria and effectively handed Turkey a win on a silver platter?
"It's hard to explain Trump's actions in Syria through the prism of what's best for American national security," Sen. Chris Murphy of Connecticut told Insider on Tuesday. "So, we're searching for other explanations. What we know is that the president has business interests in Turkey."
Read more: These are the key players you need to know to make sense of the Trump impeachment inquiryThe Democratic senator, who sits on the Senate Foreign Relations Committee, said the situation underscores the need for Trump to release his tax returns: "The American people deserve to know the extent of the president's business interests overseas so that we know whether he's making foreign policy decisions in the best interests of the country or in the best interests of his family, bottom line."
Multiple other Democratic lawmakers, including Sen. Richard Blumenthal of Connecticut and Rep. Ted Lieu of California, have raised Trump's business links in Turkey to his Syria retreat.
Citizens for Responsibility and Ethics in Washington (CREW) has also voiced concerns. "We can't ignore that the president's decision to abandon the Kurds, despite widespread backlash, could have had something to do with the property he owns and profits from in Istanbul," the ethics group said in a recent tweet.
Trump has broken from other presidents in retaining ownership of his business empire and not placing his assets in a blind trust while in office.
Read more: 8 Trump officials made stunning revelations about how the president and Giuliani weaponized the State Department-Ivanka Trump (@IvankaTrump) April 20, 2012
Trump has also been scrutinized for his financial interests in other countries, including Russia and Saudi Arabia. His frequent and repeated capitulation to the leaders of both countries has raised questions about whether the president was motivated by personal interests when dealing with them in an official capacity.
Trump's financial ties to Russia, in particular, were central to the former special counsel Robert Mueller's investigation into Russian interference in the 2016 election. They're also a key focus for the House Intelligence Committee as it conducts an impeachment inquiry looking at whether the president used his public office for private gain.