Minnesota governors can't veto proposed constitutional amendments.

But governors have bully pulpits. DFL Gov. Mark Dayton used his during last week's State of the State address to take a swipe at a bad idea that some GOP legislators want to add to the Constitution -- a ban on labor contracts that require all workers employed under the terms of the contract to pay a share of union costs.

Dayton noted that Minnesota enjoys an unemployment rate lower than four of the five states that top the conservative-backed Tax Foundation's business climate rankings. Four of those five states also ban union payment requirements.

"We must be doing something right" without that ban, Dayton said. "In fact, we're doing a lot right."

Moments later, he added a plea: "Let's not forget what has lifted us from below average to above average to outstanding. Let's not destroy good wages and benefits ... in search of another strategy of unproven value -- or one of proven less value."

That well describes the implications of a proposal that acquired the misleading label "right to work" (RTW) 65 years ago, when the federal Taft-Hartley Act gave states authority to outlaw workplaces that make union membership a compulsory condition of employment. RTW laws soon followed in union-averse regions.

Contrary to what its label implies, it would give no one the right to a job. Rather, it would allow workers in union shops the option of a "free lunch" -- the chance to benefit from collective bargaining without paying for it.

For many of the workers who might exercise that option, the free lunch wouldn't last -- because the union wouldn't last. Right-to-work laws weaken and kill unions.

Only 7 percent of workers in 22 RTW states are represented by unions, compared with 15.8 percent in Minnesota and an average of 15 percent in non-RTW states. (A 23rd state, Indiana, joined the RTW list earlier this month.)

This is not a question of enabling union opponents to exercise their consciences, or preventing workers from dropping a union they no longer favor. Federal law already protects workers who don't want to join a union from dismissal.

Workers in union shops who don't care to join are required by state law to pay an 85 percent "fair share" in lieu of union dues. Federal law provides that during a predefined period prior to a labor contract's expiration, workers can opt out of their union or change their bargaining agent.

RTW is sold as a spur to business growth, including hiring. But that flies in the face of the fact that Minnesota's unemployment rate is already lower than all but four RTW states.

Those four are all Minnesota's neighbors -- North Dakota, South Dakota, Nebraska and Iowa -- and Iowa's jobless rate is almost identical to Minnesota's at 5.6 percent. That suggests that conditions other than RTW are at play in this region's employment levels.

A study sponsored by the conservative Center of the American Experiment contends that RTW would raise wages gradually over time -- $2,360 to $3,072 more per capita in 2008, if RTW had been enacted in Minnesota in 1977.

Yet only three RTW states had higher median household incomes than Minnesota had in 2010, according the U.S. Census bureau. And 12 states whose median incomes are higher do not have RTW laws.

Given the data, it's hard not to think that Republicans like RTW for its potential to damage a powerful Democratic Party ally.

It's also hard not to think that the sudden plethora of RTW bills (18 state legislatures considered RTW in 2011) is orchestrated by corporations via the American Legislative Exchange Council, a business-bankrolled organization that feeds model legislation to conservative lawmakers around the country.

RTW represents a step away from Minnesota's economic roots and toward America's South and West. Unlike those historically low-wage regions, Minnesota has long aimed to be a high-wage, high-skill state in which the fruits of enterprise are widely and fairly shared. That sharing extends to the public schools and social services that build the future human capital a high-skill economy needs.

Robust labor unions have helped Minnesota pursue that strategy, with notable success. Weaker unions are likely to lead to lower wages and benefits, which will translate into reduced tax revenue and depleted ability for Minnesota to compete for knowledge-economy jobs.

Following RTW states would put Minnesota on a new and risky path. That's a risk legislators should not invite voters to take.