Prosecutors want a judge to impose a maximum 30-year prison sentence on a former Illinois National Guard soldier, calling his plot to attack a U.S. military facility "a contemptible betrayal of both the Nation's trust and his fellow soldiers."

A government filing Friday in Chicago federal court says 23-year-old Hasan Edmonds deserves the sentence for two counts of conspiring to provide material support to a foreign terrorist organization because "betraying one's country while in its service is a particularly grave crime."

Prosecutors say the Aurora man and his cousin, 30-year-old Jonas Edmonds, devised a plan for Hasan to join Islamic State fighters overseas while Jonas attacked a National Guard armory in Joliet.

Both pleaded guilty and will be sentenced Sept. 16. Prosecutors want a 21-year prison term for Jonas Edmonds.