Make no mistake: Republican politicians in Texas are making a monumental error.

Apparently not content with a moral or legal blunder, Greg Abbott and Dan Patrick are probably about to cost Texans at least $15 billion. With their insistence on a range of discriminatory laws, that number may be bigger and would be measured in lost revenue, wages, reputation and even college football games, not over months but years. And Texans will wind up picking up their tab.

Abbott's tenure, with Patrick, is remarkable in that it has traded bread for circuses: the Texas Republican Party has abandoned its leadership position in economic, business and fiscal matters. Instead, the governor has set forth an agenda of more restrictions on abortions, a crackdown on unauthorized immigrants, regulations on bathrooms and micromanagement of cities. These are hardly the embodiments of small government and free enterprise.

But today's Republican leadership, with the notable exception of House Speaker Joe Straus, is composed of Big Government Republicans. The only thing most Republican politicians seem interested in doing is expanding their own power. The governor wants to have a national constitutional convention that, presumably, will elevate him to the presidency. Patrick wants to culminate his transformation from a Maryland radio host to governor of the nation's second-largest state, apparently.

Yet there is no coherent ideology or governing principle. Where Rick Perry took credit for every twist and turn in the economic boom of the Texas Miracle, Abbott is presiding over a continued oil bust and an arguably flat state economy. Texas ranks 34th among states in unemployment, according to federal statistics, and we are a cellar-dweller on a range of public necessities, from education to health care. And these are factors in where business chooses to do business.

And Abbott is tarnishing Texas with a legacy of discrimination that will discourage business. This isn't just a projection; it's a fact. Unfortunately for North Carolinians, they have just lived through — and beat a hasty retreat from — just such a ludicrous and discriminatory law. And after a dozen years, The Associated Press has carefully tallied the cost: $3.76 billion.

Costs weren't just measured in canceled concerts or sporting events but expansions that never happened and jobs that went elsewhere. Paypal killed its expansion. Adidas went to Georgia. Deutsche Bank pulled the plug on moving into Raleigh. Investors instructed bankers not to invest in North Carolina bonds.

So, what about Texas? It turns out that a simple way of guesstimating the economic impact of the bathroom bill is simply to account for the difference in size between the two state's economies.

The Texas economy, at $1.6 trillion in gross state product, is about three times larger than North Carolina's. And so the prospective loss in Texas, based on the experience of North Carolina, would top $15 billion. Now, to Greg Abbott and Dan Patrick that may not be a lot of money. But they don't own a butcher shop, they don't clean rooms, park cars or drive trucks.

Yet that kind of money is, to put it into perspective, more than the output of the entire agricultural sector in a single year.

If, by now, you're wondering about my math, I checked with Ray Perryman, the state's best private economist. "It's not crazy at all," he said, merely urging me to explain, as I have, how we arrived at this figure. Indeed, Perryman's firm has published its own study projecting a loss of $3.3 billion just in the tourism and convention business alone from the bathroom bill.

In fact, the losses could be substantially higher because of the same effect of the sanctuary cities law.

"There could be a kind of stacking effect," said Daniel Court, senior economist at Eliott D. Pollack and Co. in Phoenix. Court studied the economic damage of discriminatory laws aimed at immigrants under Arizona's show-me-your-papers law.

Years after the fact, Arizona's construction industry is suffering from a tight labor market, he said; it's unclear if that's a trailing effect from its infamous racial profiling law, eventually struck down partly in court and abandoned under a settlement. In state after state that goes down the path of enshrining discrimination — no matter how cleverly done — the results are the same.

Indiana, Alabama and Mississippi have all had immediate losses in the tens of millions of dollars. And these are states with much smaller economies. The latter two are now shuddering because California universities will stop playing them in football — and Texas is on that list, too.

Texas business is opposed to legalizing discrimination against transgender people now, just as it was against enacting the sanctuary cities law. The Texas Association of Business has opposed both. Employers including AT&T, American Airlines, Southwest, Google and others oppose the bathroom bill.

But these are practical and ethical arguments that fall on the deaf ears of politicians priming their electoral base; fewer than 30 percent of Texas voters think the bathroom bill is a priority, according to the UT-Texas Tribune Poll. But that's who elects politicians in this state, often fewer than 1 million people in a state of 27 million.

Normally — especially to politicians — money talks. But not now. Then again, it's not their money they're throwing away. It's yours.

Richard Parker is a writer in Austin and the author of Lone Star Nation: How Texas Will Transform America. He is a frequent columnist for The Dallas Morning News. Twitter: @richardparkertx

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