Headlines throughout the state of Arizona are highlighting the debate on Senate Bill 1083, a bill to stand up Arizona’s modern state militia or State Defense Force (SDF).

Authorized by the Constitution and by federal law, SDFs have a long history within the United States. While their role has changed over time as the needs and threats faced by the U.S. have evolved, today’s SDFs serve as auxiliaries to the National Guard units of their states as well as force multipliers for state homeland security missions in disaster preparation, response, and recovery.

In July 2011, Arizona’s Senate Bill 1495 went into effect, authorizing the governor to establish a state guard unit or SDF. Now with S.B. 1083, the state legislature is debating exactly what role the SDF should play to advance the state’s homeland security efforts. (S.B. 1083 actually refers to the Arizona Special Missions Unit. Don’t be confused: It’s the same thing with a fancier name.)

The main sponsor of the bill, state Senator Sylvia Allen, has argued that an armed Arizona SDF is needed to help stem the tide of illegal immigration and drug smuggling along Arizona’s shared border with Mexico. S.B. 1083 also calls for Arizona’s SDF to have a mission set that includes disaster response and search-and-rescue activities.

With Arizona having suffered the largest wildfire in state history just last year, the later mission set clearly make sense. In fact, in recent years SDFs have proved instrumental in aiding state and local leaders in disaster response, particularly in the aftermath of both September 11 and Hurricane Katrina.

While few have questioned this mission set, however, the call to allow Arizona’s SDF to assist state and local law enforcement agencies in border security operations has many up in arms. Many have expressed concern about ensuring that SDF members have sufficient training and oversight in carrying out such a mission. Any SDF border-security contingents must respect the three main tenants of volunteer activity: (1) liability, (2) accountability, and (3) sustainability. However, with these conditions met, states should be allowed to decide which missions their SDFs will fulfill.

Arizona’s SDF would become the 24th active SDF in the U.S. As a low-cost force multiplier for homeland security, an SDF has much to offer the state. In establishing the force, however, Arizona must carefully decide the needs of the state and where an SDF can add the greatest value to Arizona’s homeland security enterprise.