What Mattered This Week: March 9-13, 2020

President Trump declared a national emergency on Friday after banning most travelers from Europe, ending a week upended by the coronavirus pandemic. Plus, former Vice President Joe Biden solidified his campaign's resurgence with wins in four states on Tuesday ahead of a debate with Senator Bernie Sanders on Sunday in Washington, D.C. Read up on these and more of the week's top headlines.

What Mattered This Week: March 9-13, 2020