Extra points if your colonialism exploits an internecine conflict such that it appears that internal problems of the country, rather than exogenous meddling with state or tribal sovereignty, led to it's failure to govern (reinforcing how "correct" your form of government is)

Pretty much yeah, and if that fails, sanctions and economic wars

It didn’t go out of fashion. Industrialization made wars of conquest unprofitable by 1890-1910 or so, and it took the world that long to get a clue. (Russia, notably, still hasn’t figured it out.) If you build one factory, you make money; if you build an army to steal your neighbor’s factory, most likely you both get zero factories.

Of course, it's much easier and cheaper these days to use your intelligence services to stage a coup in that country so that your corporations can get their bananas for free, or, planting fake WMD intelligence at the UN so you can justify going in guns blazing and your corporations can make money through weapons sales, oil extraction, logistics and reconstruction on the back of taxpayers and the intelligence services by running heroin to fund their black ops.

In modern warfare, you don’t get these for free. If you’re trying to yoink from a fellow nation-state, you risk your own factories being bombed. If you’re up against a less sophisticated foe, you still sacrifice industrial production and diplomatic goodwill in excess of any base resource gains.

It’s cheaper and more fruitful to trade for those goods than it is to steal them. (Coups are no exception. They disrupt the economy and jeopardise the security situation. Much simpler to trade with Tehran than try for a coup that doesn’t result in civil war or blowback.)

Which tends to have effects similar to what you've described. Land that isn't near a potential threat can be invested in much more heavily. Borders are easier to defend, etc.

But improvement to existing resources tends to be more attractive to those with the most resources already.

To wit: “…much of [balance-of-power politics] theory was based on agrarian states or early industrial states. And one of the features of agrarian interstate relations was that returns to war outpaced returns to capital, which is a fancy way of saying you could get richer, faster by conquest than by development. Under those sorts of conditions, most powers were going to be, in some form, ‘revisionist’ powers because most powers would have something to gain by attacking a weaker neighbor and seizing their resources (mostly arable land and peasant farmers to be taxed). Indeed that basic interaction creates much of the ‘churn’ of interstate anarchy: everyone has an incentive to prey on their neighbors, creating the dog-eat-dog brutality of interstate interactions. The only countries without such an interest would be countries that were very small and weak, seeking to avoid being absorbed themselves.

But, as we’ve discussed, industrialization changes all of this: the net returns to war are decreased (because industrial war is so destructive and lethal) while the returns to capital investment get much higher due to rising productivity. In the pre-industrial past, fighting a war to get productive land was many times more effective than investing in irrigation and capital improvements to your own land, assuming you won the war. But in the industrial world, fighting a war to get a factory is many, many less times more effective than just building a new factory at home, especially since the war is very likely to destroy the factory in the first place. This was not always the case! The great wealth of many countries and indeed industrialization itself was built on resources acquired through imperial expansion; now the cost of that acquisition is higher than simply buying the stuff. War is no longer a means to profit, but an emergency response to avoid otherwise certain extreme losses.

So whereas in the old system, almost every power except potentially the hegemon, had something to potentially gain by upending the stability of the system, the economics of modern production means that quite a lot of countries will have absolutely nothing to gain from a war, even a successful one. Now that dispassionate calculation has arguably been true for more than a century; the First World War was an massive exercise in proving that nothing that could be gained from a major power war would be worth the misery, slaughter and destruction of a major power war. Subsequent conflicts have reinforced this lesson again and again, yet conflicts continue to occur. Azar Gat argues in part that this is because humans are both evolved in our biology (and thus patterns of thinking and emotion) as well as our social institutions, for warfare and aggression. We have to unlearn those instincts and redesign those institutions and this process is slow and uneven.”

https://acoup.blog/2023/07/07/collections-the-status-quo-coa...

And yet the "war on terror" happened. US companies gained a lot from that even if the average taxpayer didn't.

The War on Terror, and invasion of Iraq, were massive American policy failures. Had Xi not become a dictator and Putin not invaded Crimea and then the rest of Ukraine, American hegemony would be on a downturn as a result of those fumbles.

Not if you ask Halliburton

The stockholders who have seen a third against since 2006?

You’re dragging a red herring. In the past, conquest was popular because it made the conqueror as a whole rich. Today, you’re limited to scratching out whatabouts with one-off and dated examples like Halliburton. The circle of net beneficiaries rivals that of botched aid operations.

Compare this to wars of Ancient Rome which were actually popular, because they brought home visible wealth.