Today is Labor Day in the United States, a holiday that celebrates workers and the labor movement (it also celebrates hamburgers, if most people’s Labor Day activities are anything to go by). Unionization doesn’t make sense for most superheroes (they work for free, after all), but there are some exceptions. For example, in some continuities the agents of S.H.I.E.L.D. are basically federal employees, and many federal employees are union members. Although some superheroes who work for S.H.I.E.L.D. / the Avengers don’t have much use for a union (e.g. Tony Stark is independently wealthy and Thor is a god), folks like Nick Fury are regular employees for whom union benefits would be pretty appealing, and there are countless non-superhero employees working in the background.
So could S.H.I.E.L.D. unionize? Maybe, maybe not.
Federal employee unions are governed by the Federal Labor Relations Act (whereas most unions are governed by the National Labor Relations Act). However, the FLRA specifically excludes certain agencies from coverage, including the FBI, the CIA, the NSA, and the Secret Service. The exclusion of these law enforcement and espionage agencies suggests that S.H.I.E.L.D. might be excluded in the Marvel Universe. On the other hand, however, some other law enforcement and defense agencies are unionized or in the process of unionizing, including the Transportation Security Administration, the National Park Service, the Border Patrol, the Bureau of Alcohol Tobacco and Firearms, and the Department of Defense (the civilian workers, not the armed forces, which are forbidden from unionizing by 10 USC 976). So it’s possible that S.H.I.E.L.D. employees could unionize.
In general the FLRA works like the NLRA, although federal unions cannot create “union shops” in which employees are required to join the union in order to work for the agency. They also cannot strike. Thus, S.H.I.E.L.D. employees could always choose not to join the union. The benefits of a union formed under the FLRA include collective bargaining rights, the right to file grievances, and the right to protection from unfair labor practices. Like most unions it would probably be more concerned with working conditions and compensation for regular workers than, say, hazard pay for fighting Kang the Conqueror.
From a comic book writer’s perspective it’s unfortunate that federal employee unions can’t go on strike. Otherwise it might lead to some pretty funny scenarios. Can you imagine the Avengers forming a picket line or the government bringing in some B-list superhero scabs?
Update: Over at Abnormal Use they have a class Justice League cover featuring striking superheroes.