It was a true “candidate of change” who rescued the U.S. from the doldrums of the ’70s. “Reaganesque lower taxes and deregulation,” economic historian John Steele Gordon wrote in The Wall Street Journal recently, “sparked an enormous economic boom that has now lasted, with two brief and shallow recessions, for more than 25 years.”

The rest of the world learned Reagan’s lesson, too. Most countries slashed tax rates after we did, and generated growth of their own. By reversing that policy, Sen. Obama would put the U.S. in with an ever shrinking group of nations that cling to the failed policies of the past, and are suffering for it.

Only six of the top 30 industrial nations have a tax rate for all levels of government combined that adds up to more than 55 percent. Obama’s tax plan would give us a higher top rate than such high-tax nations as Sweden and Denmark. And these sorts of tax rates slow the economy.

Among those six high tax countries the average unemployment rate is 7.35 percent. Contrast that with our own unemployment rate, which recently rose to 5.5 percent -- still a low figure by historic standards.

The math is simple: Lower tax rates encourage more economic growth and lower unemployment. Higher tax rates lead to slower growth and lower wages. In 2001 and 2003, President Bush pressed Reagan’s tax-cutting policies even further, slashing tax rates and boosting the economy into several more years of growth. The sensible policy today would be to make those cuts permanent, so business owners and entrepreneurs could plan for the future.

The only other option is a return to the discredited policies of the ’70s. And that’s a change we simply can’t afford.