WASHINGTON — When David Ensor announced last week that he was stepping down as the director of the Voice of America, critics saw the move as the latest sign of turmoil at the government agency that is charged with presenting America’s viewpoint to the world.

The resignation came just weeks after Andrew Lack, the first chief executive of the Broadcasting Board of Governors, which oversees the Voice of America, left 42 days into the job to take a post at NBCUniversal.

Lawmakers, foreign policy experts and former staff members say the Voice of America is floundering at the very moment when America needs to counter sophisticated propaganda machines that have expanded the influence of countries like China and Russia and terrorist groups like the Islamic State.

“We are getting our butts kicked,” said Glen Howard, the president of the Jamestown Foundation, a Washington think tank. “Countries like Russia are running circles around us, and our international broadcasting is in disarray.”