When we think of herd immunity, we think of vaccinations.  Fewer parents are vaccinating their children nowadays because of their fears about negative reactions to vaccinations (including the now-debunked theory about vaccinations causing autism).  Those parents skipping vaccination point triumphantly to the fact that, despite their children’s vaccination-free status, there hasn’t been a huge upsurge in measles, mumps, rubella, polio, chickenpox, or any of the other diseases that can now be prevented with a shot or nasal mist.

What these parents fail to realize is that the diseases haven’t stopped simply because they’re rare; instead, they’re rare because other children are getting vaccinated.  Because there are a sufficient number of immunized children within a given population, these former childhood scourges cannot the necessary foothold to become endemic or epidemic.  It’s this perfect balance — where just enough kids are vaccinated to defeat a disease’s onslaught — that we call herd immunity.  This balance is also very tenuous.  If the number of vaccinated children drops below the magic herd immunity point, dangerous diseases come back in a hurry.

Accepting the unions’ premise that unionization is a good thing, one can apply the same argument.  The opposite of right-to-work laws is mandatory unionization.  That means that, if you want to work in a specific industry, whether as an electrician or a teacher, you must join the union.  The theory behind this is that unions are so good at ensuring that workers are well treated, that all workers benefit and all workers should therefore contribute to the union.  It wouldn’t be fair for some workers to pay dues, and then for all workers to benefit.

Just as with vaccinations, however, a lot of workers lately have been complaining about the side effects from the unions’ role in their industries.  These side effects include economic demands so parasitical that they kill the host and the unions’ habit of going far beyond their initial mandate, so that union members find their funds supporting political ideologies that are antithetical to their own beliefs.  In right-to-work states, these people are allowed to opt out.

The union screeches are because they believe that it is unfair for non-union members, in effect, to benefit from herd immunity.  They don’t have to suffer from the downside of unionization (i.e., paying dues), but they get the upside benefits (i.e., better employment conditions).

The thing is that unions are not vaccinations and working conditions are not diseases that can become epidemic or even pandemic.  Instead, there is a marketplace balance:  if too many people don’t join the union, breaking part the herd immunity, the marketplace will shift.  In that case, rather than inevitably getting worse as happens when a toxic disease breaks out, things might actually get better or they might get worse, or they might just get different.

Tradeoffs are not the same as a polio pandemic.  As Charles Krauthammer points out, union states have higher wages and lower employment; right-to-work states have lower wages and higher employment.  In other words, both systems have benefits and both have failings.  The employees ought to be able to determine which system they prefer at a given workplace.

Having the government impose mandatory union membership perverts the marketplace and prevents workers from making choices about the system that works best for them.  Certainly, given union threats and hysteria, one suspects that the unions are worried that they won’t be able to compete in a free market.  With increasing worker mobility and communication skills, we don’t have the stagnant local employment market that allowed 19th and early 20th century employers to abuse a trapped labor market.