If we can agree that one definition of insanity is the impulse to utter the same idiocy over and over, then I'll offer these items as evidence:

On Aug. 24, 2015, Donald Trump said, "We're the most highly taxed nation in the world."

On Feb. 6, 2016, Trump said, "Right now we're the highest taxed nation in the world."

On Feb. 25, 2016, Trump said, "America has the highest taxes anywhere in the world."

On May 8, 2016, Trump said, "We're the highest taxed nation in the world."

On June 21, 2017, Trump said, "Really, on a large-scale basis, we are the highest taxed nation in the world."

On July 25, 2017, Trump said, "We have the highest taxes in the world."

On Aug. 10, 2017, Trump said, "We pay more tax than anybody in the world."

Yesterday morning Trump said, "We are the highest taxed nation in the world."

He lied every time.

Maybe he knows he's lying, or maybe he simply believes that whatever passes his lips is automatically rendered true. Either way, his end game is obvious. Tax analyst Robert Goulder, writing on a Forbes magazine blog, puts it best: "If the masses can be convinced that they're grossly overtaxed relative to everyone else in the world, the case for tax reform becomes easier — or at least for tax cuts."

And as evidenced by Trump's skeletal tax reform wish list, these would be tax cuts aimed heavily at the top income brackets and tax cuts for the richest corporations, all of which would drain federal revenue and profoundly deepen the deficit. To achieve those goals, lying to the public - telling Americans that they're the most overtaxed people on the planet — is all part of the plan.

We all know it's futile to fact-check Trump — after all, he eked out his Electoral College victory despite rigorous fact-checking of his serial lies - but just in case there's anyone out there who's still on the fence about the guy, or who's perhaps wary of his current promise to cut taxes for a middle class that's supposedly the most overtaxed middle class in the world, let's do it anyway. If only to remind ourselves that even here in Trumplandia, facts still matter.

Goulder, the Forbes contributor, can start us off: "In reality, the United States is among the least-taxed nations within the OECD." He was referring to the 34 industrialized nations that comprise the Organization for Economic Cooperation and Development. The OCED's most recent stats, for 2014, measure tax revenue as a percentage of GDP. The average, among all OECD nations, is 34.2 percent. America's percentage — 26 percent — ranks 31st of the 34 nations. America's overall tax burden is higher than only three nations: Korea, Chile, and Mexico.

Those stats have been vetted by the bipartisan Committee for a Responsible Federal Budget, which concluded last year: "As a share of the economy, the United States is nowhere close to the 'highest-taxed country in the world' and does not raise nearly as much tax revenue as other developed countries."

Meanwhile, also in '16, the Pew Research Center crunched the OECD's tax stats to compare American families with those in other western nations. Their findings mirrored the consensus:

"We chose to focus on a simple measure of tax burden - national-level income taxes plus mandatory social-insurance contributions as a percentage of gross income. We calculated this for four different family types: a single employed person with no children; two married couples with two children, one with both parents working and the other with one worker; and a single working parent.

"In all cases, the U.S. was below the (OECD) average — in some cases, well below."

For instance: "A single, childless American making the average wage in 2014 ($50,099), for instance, paid 24.8 percent of her gross income in federal income tax and payroll taxes, versus the (OECD) average of 27.3 percent. Such a person living in Belgium, by contrast, would pay 42.3 percent of her gross income. An American married couple, both working (one at the average wage, one at two-thirds of it) and with two kids, paid 19.4 percent of their gross income in taxes; a similar Belgian family would have paid nearly double that rate, or 38.3 percent."

But what about America's corporate tax burden, which Trump also touts as the heaviest in the world? In truth, it's nowhere near the worst. Measuring corporate tax revenue as a percentage of GDP, stats from the OECD rank America 17th - the middle of the pack. Another study, conducted last year by the World Bank and PricewaterhouseCoopers, looked at the potential tax burden, as a percentage of total profit, for a hypothetical company that could locate anywhere in the world. The two organizations concluded that America ranked 64th of 189 nations.

Trump will nevertheless chant his false mantra in the months to come, as his tax-cut quest gathers steam (assuming he can work with the increasingly disaffected congressional GOP), and alas, the truth is typically far more nuanced than the oft-reiterated lie. But surrendering to the lie is not an option. The truth, when vigilantly administered, can still be effective in the fight against rhetorical insanity.

-------

Follow me on Twitter, @dickpolman1, and on Facebook.