Whatever Republican economic theory has asked of Georgia, Georgia has delivered.

Even though our economy is built upon transportation, we have slashed spending to such an extent that we are 50th in the country in per capita spending on highways, transit, etc. And as Gov. Nathan Deal proudly noted during his State of the State address in January, that’s true across the board:

“According to the Tax Foundation, Georgia has the lowest tax burden on its citizens of any state in the nation,” Deal bragged. “I don’t know about you, but I see that as a good thing, and I will fight to keep it that way!”

Deal will be pleased to learn that since that speech, the Tax Foundation has released updated data, and Georgia retains its coveted spot of 50th in state revenue per capita. In fact, we collect almost $1,000 less per capita than Alabama, and more than $2,000 less per capita than Mississippi.

(Although we like to flaunt our supposed independence from Washington, the Tax Foundation also reminds us that thanks to low state taxes, we depend on the federal government for some 38.9 percent of our state budget, the eighth highest rate of federal dependency in the country.)

Those low taxes come with other costs as well. When a winter storm hits, we lack the equipment or manpower to clear the highways, leaving commuters stranded for days. When a recession hits, we fire teachers by the thousands and shorten the academic year. We slash funding for higher education, cut health care for state employees and lay off hundreds of social workers assigned to protect vulnerable kids from abuse or worse, rushing to rehire them only after the body toll grows too high to ignore.

Why? Because we’re told there’s a rainbow out there somewhere. By slashing taxes and slashing taxes and slashing taxes, the theory goes, we create a pro-growth environment that will attract industry and high-paying jobs, boosting the standard of living for everyone. That has been Georgia’s approach to economic growth since the 1870s and 1880s, when men such as Henry Grady began trying to lure northern industry to the post-war South with low wages and low taxes, and it remains the strategy today.

In effect, we’re applying a 19th century industrial strategy to a 21st century economy, then wondering why it isn’t working. Because it isn’t. By any number of metrics — poverty, income, jobs — we’ve been losing ground for 15 years. Since 2003, for example, the national gross domestic product has grown by 22 percent; in Georgia, it has grown by just 13 percent.

And while the reasons are complex, here’s a start: In a global economy that rewards a high quality of life, a modern transportation infrastructure (including transit), and effective health care and educational opportunity for all, we take pride in funding none of those things.

That isn’t Nathan Deal’s fault. Long-term problems of this sort can’t be blamed on a governor who has yet to complete his first term. But it becomes his fault — and more accurately our fault — if we refuse to change that approach. When you’re 50th in the nation in state revenue per capita, how much farther down that dead-end road can you travel before you realize that maybe, just maybe, you missed a turn a decade or so back.