Story highlights Bergen and Sterman: Wednesday's shootings are possible act of leftist terrorism

In the 1960s and 1970s, left-wing terrorism was a common occurrence in the United States

Peter Bergen is CNN's national security analyst, a vice president at New America and a professor of practice at Arizona State University. He is the author of "United States of Jihad: Investigating America's Homegrown Terrorists." David Sterman is a policy analyst at New America's International Security Program.

(CNN) On Wednesday morning, a gunman attacked congressional Republicans practicing baseball, injuring five people including House Majority Whip Steve Scalise. The man identified as the shooter, 66-year-old James T. Hodgkinson III, was taken into custody and later died.

Peter Bergen

David Sterman

While the incident remains under investigation, a review of Facebook pages belonging to Hodgkinson show he supported Sen. Bernie Sanders during the election and was fervently opposed to President Donald Trump. One Facebook post read: "Trump is a Traitor. Trump Has Destroyed Our Democracy. It's Time to Destroy Trump & Co." Sanders confirmed that Hodgkinson had volunteered for his presidential campaign and, in no uncertain terms, condemned his violent acts.

Two Republican congressmen who were at the baseball practice, Florida Rep. Ron DeSantis and South Carolina Rep. Jeff Duncan, also said that a man who looked like the shooter had asked them before the shooting if the players were Republicans or Democrats. Duncan replied they were Republicans.

Hodgkinson's political leanings, his potential targeting of GOP victims and the symbolic importance of those victims raises the very strong possibility the shooting was an act of leftist terrorism.

Hodgkinson's attack appears to fit the commonly accepted definition of terrorism, which is politically motivated violence against civilians by an entity other than a state, and once again reminds us that terrorism is the province of no single ideology.

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