What is the Jade Helm military exercise?

A massive military exercise planned in states across the American West has touched off a political firestorm, with several top Texas officials now questioning the military’s plans – if only to calm the Internet and constituent furor surrounding it.

The seven-state war simulation exercise, known as “Jade Helm 15,” is planned for July 15-September 15, 2015. It involves training exercises on private and public land – while such exercises are hardly unique, even the military acknowledges the “size and scope” of this one sets it apart.

According to the FBI, three men arrested in Gaston County believed in the Jade Helm conspiracy, and were arming themselves to fight against the U.S. Government should it impose martial law.

Walter Litteral, Christopher Campbell, and Christopher Barker were arrested after Campbell's tattoo parlor in Belmont was raided Saturday.

Some of the Jade Helm exercises will be held in counties across Texas, which is the state in which Walter Litteral's son lives. Litteral is facing federal charges for receiving or possessing explosives, conspiracy against the U.S., and other charges.

While the White House and Pentagon are downplaying concerns, this hasn’t stopped a barrage of blogs and tweets warning about whether the federal government is preparing for “martial law.” Even actor Chuck Norris is keeping his “eyes of a ranger” on the situation.

Western-state officials are now caught between a desire to calm their residents – and yet not appear to stoke any conspiracy theories.

More on this story from FOX News.

Groups of wary citizen watchdogs are keeping an eye on the exercises. 

Pete Lanteri, a former Marine now living in Arizona, told FoxNews.com that volunteer members he's helped organize will be on the ground as part of a newly formed surveillance campaign called “Counter Jade Helm.” A product of mounting suspicions across western states over the exercise itself, the group has been set up to locate, track and observe U.S. soldiers – Green Berets, Air Force Special Ops, Navy SEALs -- training across the Southwest.