Barack Obama' exploding fist pump On his way to the podium, he spied Illinois Senator Mark Kirk in the crowd. Mr Kirk has just returned to the Senate after recovering from a stroke suffered over a year ago. Nudging Joint Chiefs of Staff chairman Martin Dempsey aside, he offered Mr Kirk a fist bump. In a show of true bipartisanship, the Republican senator did not simply return it but turned it into an exploding fist bump. The gesture was not shown on live TV but was picked up from a pool feed by website Gawker, who turned it into an animated video clip. The American media have christened it the "Exploding bipartisan fist bump." President Obama is, however, no stranger to the gesture. Last year he was caught giving another exploding fist bump to an American serviceman in Afghanistan.