WASHINGTON, Sept. 21 (Xinhua) -- U.S. President Donald Trump on Saturday threatened Afghanistan with "bad things" if it doesn't "give Bagram Airbase back." "If Afghanistan doesn't give Bagram Airbase back to those that built it, the United States of America, BAD THINGS ARE GOING TO HAPPEN!!!" Located about 50 km north of Kabul, the Bagram Airbase was the hub of U.S. and NATO operations during the two-decade-long War in Afghanistan. During his recent visit to Britain, Trump said that the United States is "trying to take back" the Bagram Airbase. The remarks have attracted widespread attention and sparked speculation about whether the United States intends to redeploy troops to Afghanistan.