Russia testing Biden resolve in Syria amid string of 'unprofessional' incidents

Russia has been involved in a string of "unprofessional" incidents involving U.S. forces in Syria, raising fears over Washington's ability to deter Russia in the country.

Roggio's comments come just days after a Russian fighter jet buzzed a U.S. surveillance craft in the skies over Syria, an incident that put the lives of the four American crew members in danger, according to the Pentagon. Michael Lee is a writer at Fox News. Follow him on Twitter @UAMichaelLee

The close call was just one in a string of incidents in Syria in which Russian troops have tested their American counterparts with seemingly no fear of consequences. Earlier this month, the Pentagon released footage that showed Russian aircraft flying close to and deploying flares around multiple U.S. drones. A day earlier, Russian SU-35 fighters flew right into the flight path of U.S.-operated MO-9 Reaper drones and forced the unmanned aircraft to take evasive action.