When the federal government spends more than it collects in taxes, which it does most years, it has to borrow money to make up the difference. That gap is the federal deficit, which is expected to top $1 trillion in 2019. Alyson Hurt/NPR hide caption
President Trump meets with congressional leaders in the Oval Office at the White House on Sept. 6. The deadline to fund the government and raise the debt ceiling is coming up on Dec. 8. Alex Wong/Getty Images hide caption
President Trump meets with Senate Majority Leader Mitch McConnell, R-Ky., Senate Minority Leader Chuck Schumer, D-N.Y., House Minority Leader Nancy Pelosi, D-Calif., and other congressional leaders in the Oval Office. According to The Washington Post, Trump and Schumer have agreed to work on a plan to eliminate the debt ceiling. Evan Vucci/AP hide caption
White House Budget Director Mick Mulvaney leaves a Republican strategy session in which he and Treasury Secretary Steven Mnuchin were blasted by lawmakers over President Trump's deal with Democrats. J. Scott Applewhite/AP hide caption
President Trump meets with Senate Majority Leader Mitch McConnell and House Speaker Paul Ryan during a budget discussion in March. Chip Somodevilla/Getty Images hide caption
The Senate passed a bill to fund the government for two years. The measure suspends the debt ceiling and allocates $80 billion to domestic and defense programs. Jacquelyn Martin/AP hide caption
Preparations underway in the Media Center at the third Republican debate on the campus of the University of Colorado in Boulder, Colo. Robyn Beck/AFP/Getty Images hide caption
Unless Congress raises the debt limit by Nov. 3, the U.S. Treasury may be left with only incoming taxes and fees to cover expenses, which would not be enough to pay all bills. Mandel Ngan/AFP/Getty Images hide caption
He's known for tears, but at his press conference announcing his resignation, Speaker John Boehner seemed almost giddy. Chip Somodevilla/Getty Images hide caption
A woman looks on at the U.S. Capitol in 2013 after the most recent government shutdown. Congress has made no progress toward avoiding a government shutdown when it will run out of funding Sept. 30. Jacquelyn Martin/AP hide caption
House Speaker John Boehner, Majority Whip Kevin McCarthy (left), and Majority Leader Eric Cantor (right) were among the 28 Republicans whose votes made it possible for most other Republicans to vote against the debt ceiling hike. J. Scott Applewhite/AP hide caption
House Speaker John Boehner and his fellow Republicans could give President Obama the clean debt ceiling increase he wants but not for the reasons the president wants it. J. Scott Applewhite/AP hide caption
Senate Minority Leader Mitch McConnell delivers remarks during a news conference in December, where he commented on the Ryan/Murray budget, debt ceiling and XL Pipeline. Shawn Thew/EPA/Landov hide caption
Wisconsin Rep. Paul Ryan, the House Budget Committee chairman, walks to a GOP meeting Tuesday. Evan Vucci/AP hide caption
Speaker of the House John Boehner during a news conference with members of the House Republican leadership at the U.S. Capitol on Thursday morning. Win McNamee/Getty Images hide caption
House Speaker John Boehner shows his softer side Thursday before resuming his tough guy role in the fiscal fight. Evan Vucci/AP hide caption
Treasury Secretary Jack Lew testifies during a Senate Finance Committee hearing on Thursday. Mark Wilson/Getty Images hide caption
At a Tuesday news conference, President Obama underscored Democrats' refusal to negotiate with Republicans on bills to reopen the government and raise the debt ceiling. Charles Dharapak/AP hide caption
Despite all the warning signs, U.S. leaders continue to barrel toward a debt default with no one yet willing to step on the brakes. SAUL LOEB/AFP/Getty Images hide caption
Treasury Secretary Jacob Lew leaves the Capitol after a visit on Thursday. Alex Wong/Getty Images hide caption
House Speaker John Boehner of Ohio (right) leads members of Congress as they step outside the Capitol on Wednesday to attend a ceremony in remembrance of the Sept. 11, 2001, terrorist attacks. With him are House Minority Leader Nancy Pelosi and House Minority Whip Steny Hoyer. J. Scott Applewhite/AP hide caption