WASHINGTON - President Donald Trump says U.S. troops "will fight to win" in Afghanistan. And he's using his prime-time address to the nation to offer a "clear definition" of victory.

  

Trump says victory in Afghanistan will mean "attacking our enemies" and "obliterating" the Islamic State group. He's also vowing to crush al-Qaeda, prevent the Taliban from taking over the country, and stopping terror attacks against Americans.

  

Trump is discussing his strategy in Afghanistan, and noting the frustration that many Americans have about the 16-year war.