Sens. Mike Lee (R-Utah) and Tim Kaine (D-Va.) on Tuesday raised concerns over President Trump's decision on Monday to deploy 1,000 U.S. troops to the Middle East. The letter asks him to clarify several aspects of the decision, including where, specifically, the troops will be deployed, what their mission is, and if they'll be used to apply pressure on Iran. They also asked Trump to relay to them what the "new, specific imminent threat from Iran is." Sens. Jeff Merkley (D-Or.), Bernie Sanders (I-Vt.), Chris Murphy (D-Ct.), and Rand Paul (R-Ky.) co-signed the letter. They emphasized that Congress has not authorized hostilities against Iran. The State Department said the troops were "for defensive purposes to address air, naval, and ground-based threats in the Middle East."

President Trump will officially launch his re-election campaign at a rally in Orlando, Florida, on Tuesday night, pitching himself as a political outsider who has kept his promises during his 29 months as president, according to advisers. Trump has already described his audience Tuesday night as record-setting, and he is expected to fill the 18,500-seat Amway Center. Trump will be joined onstage by wife Melania Trump, Vice President Mike Pence, and members of his family and 2016 campaign. Trump is struggling in the polls, both public and leaked internal ones, and his approval rating has hovered around 40 percent all term. His campaign says Trump is in good shape and will tout the strong economy and his actions on taxes, military spending, and judges.

Acting Secretary of Defense Patrick Shanahan will not go forward with his confirmation process for the full, permanent position, President Trump tweeted on Tuesday. Army Secretary Mark Esper will step into the temporary role. Reports published by USA Today and The Washington Post reveal a history of alleged domestic abuse in Shanahan's family. The FBI has investigated a violent 2010 dispute between Shanahan and his then-wife, Kimberley, in preparation for what would have been Shanahan's confirmation hearing. Additionally, in 2011, Shanahan's oldest son, William, who was then 17, assaulted his mother with a baseball bat. Kimberley required surgery as a result of the incident. Shanahan reportedly defended his son, writing in a memo that he acted in self-defense. He told the Post, however, that he never believed William's violent act was justified.

President Trump on Tuesday announced plans to meet with Chinese President Xi Jinping next week at the G-20 summit in Osaka, Japan, as the two look to hash out a deal between the U.S. and China amid an ongoing trade war. Washington and Beijing had previously engaged in talks, but they recently broke down; a Trump-Xi meeting in Osaka has been seen as a chance to rekindle the negotiations. Chinese officials have not yet confirmed the plans. Trump's tweet was enough to give a boost to U.S. stocks, signaling a sense of relief from investors who are concerned that the promises of eye-for-an-eye protectionist trade policies being doled out by both sides could have negative long-term effects on the global economy.

Facebook announced on Tuesday its first foray into digital currency, saying it will roll out cryptocurrency "Libra" next year. The coin, which uses blockchain, will be eligible for use on Facebook as well as other websites. Facebook's stock surged after the announcement, increasing by 2 percent in pre-market trading Tuesday. More than two dozen companies are backing Facebook's cryptocurrency venture, including Mastercard, PayPal, and Uber. The coin will be managed by the Geneva-based company Libra Association, of which many of Libra's backers are already members.