America is an (carbon) empire.
Venture capital-turned-polity in 1776. Like all capital, it was preordained to grow. By 1803 it made us stewards of the continent. Twenty years later, the hemisphere. Half of the remaining world in 1947 and the rest in 1991. Space back in 1983. And the world's future by 2000, thanks to assurances of an 'American Century' and our right to preemptive war. (Though it might not last a century if we do.)
For now, we sit atop the heap. So long as life still gets counted in petrodollars.
Back in 1893, as railroads were exhausting the continental market, the historian Fredrick Turner wrote a prescriptive analysis:
At the end of a hundred years of life under the Constitution, the frontier has gone, and with it the first period of American history. The people of the United States have taken their tone from the incessant expansion which has not only been open but has even been forced upon them.... He would be a rash prophet who should assert that the expansive character of American life has now entirely ceased. Movement has been its dominant fact, and, unless this training has no effect upon a people, the American energy will continually demand a wider field for its exercise.[i]
'Not only open but forced on them...' Probably not intended, Turner made a fine assessment of our democracy; a secondary exercise listed first. Five years later, when Teddy Roosevelt 'took' (his word) Cuba, Puerto Rico, and the Philippines, from Spain, democracy wasn't his motive.
But in 1904, he changed tack. The world should rent its sovereignty, rather than have us take it. In his terms: "If a country keeps order and pays its obligations, it need fear no interference from the United States." (Mind, the Philippines remained ours until 1946. Puerto Rico, though neglected, remains ours, and Cuba continues to pay dearly for its peaceful coexistence. So, nothing came off the table.)
It took until 2003 for then-proxy-president, Dick Cheney, to make clear the world would pay us to invade it, too. No rash prophet, Trump thinks now it should pay for its own prison wall.
And not least, in 1974 Nixon stipulated, whether conditionally free, or imprisoned, or bombed to dust, that it pay us in petrodollars, in effect making us the world's first carbon empire.
And what became of democracy? Arguably, the 1923 Monroe Doctrine had an anti-imperial concern for the Bolivian Revolution. Yet in 20 more years, notably while democratic revolutions were the fact of imperial Europe, it prefaced our own conquest of Mexico. Later, not coincidentally the same year Roosevelt sent out rent notices, what remained of Mexico declared war on its foreign-dealing leaders. The US sent troops to quell the insurrection but could not catch Poncho Villa. Peace in 1917 begat the world's first socialist constitution, which, unlike our liberal constitution, secured public lands, labor rights, cheap and secure credit, and ownership of natural resources.
In 1938 President Lazaro Cardenas strengthened Mexico's footing by nationalizing its oil reserves. US companies pleaded for an invasion, but Cardenas had an ally in FDR, who did not get along with the oil magnates, and did not want to push away Mexico, considering the geopolitical thrust of that era.
Over the next 3 decades, added oil revenues went to modernizing other sectors of the economy, as well as increasing education, transportation, and healthcare. Yes, as in Venezuela today, corruption was an issue. However, unlike with the preferred, neoliberal model, it's corruption because there were laws against it.
Notably, Venezuela, then, was conspicuously under-developed due to its near-complete dependence on oil revenues, which were held largely by US firms. (Even the far left, today, in blaming Chavez for the current crisis, overlooks that he was the first to substantially reinvest in other sectors of Venezuela's economy.) Mexico, with relative control of its reserves, tried to avoid that fate.
Still, a progressive constitution and some oil revenue was not equal-footing for doing business with the US. On through the '70s, when prices fell, oil reinvestments were supplemented by loans, and when oil prices fell starkly in the later years, Mexico submerged, but primarily because in 1979 the US devalued the peso. By 1982 Mexico couldn't scrounge the rent and the US and its World Bank and IMF vivisectors carved slices out of Mexico.