Investigations of the 9/11 attacks show that a short, unstable transition between two presidents can weaken U.S security. Trump's sweeping staff changes compound the risk, experts say.
President Trump has claimed the Islamic State was completely defeated on his watch – but an analysis of government maps and other reports shows his administration did only half the work.
"Where appropriate, we intend to seek justice on behalf of those in uniform," the subcommittee chairs said while announcing their probe of the Texas Army base.