Thirteen years ago almost to the day, Oklahoma City bomber Timothy McVeigh was executed on June 11, 2001.
But political scientist and security policy expert Dr. Colin P. Clarke of the nonpartisan think tank Rand Corp. says homegrown terrorism remains a "constant" threat to this day.
"The threat ... is constant. Whether or not these threats manifest themselves into attacks, it really depends," Clarke told Ed Berliner Thursday on Newsmax TV's
Clarke, who earned a Ph.D. in international security policy from the University of Pittsburgh, says "the threat of homegrown terrorism is a little more complex" today than it was in 1995 when McVeigh bombed the Alfred P. Murrah Federal Building in Oklahoma City.
"You have the homegrown jihadist threat that's linked into the broader al-Qaida or kind of local Salafist movement and then there's the threat from . . . right-wing militia type groups, groups that McVeigh was from," he explained.
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Clarke said that one advantage we have today is social media.
"People actually talk about their intentions more often than you'd think," he explained.
Jerad Miller, who killed two police officers and a civilian in Las Vegas last Sunday before his wife Amanda killed herself and police shot Miller to death, is among those who disclosed his thoughts via social media on his Facebook page, Mediaite reported.
However, Clarke said social media can also be misleading.
"For every guy like Miller that's out there, there are probably dozens that are saying the same things but are actually never going to do anything about it," he said.
"So it's more about identifying who these individuals are and if they're going to make it easy for law enforcement by posting these things," Clarke said.
"Great, let's take advantage of that," he added, "but it's difficult to stop every attack."
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