[anonymouskimmer]

A couple of possible reasons:

1) It takes time for countries to break old habits when it comes to war.

2) Probably most important for WW1, the personal wealth of monarchs is in the lands they own, not the industries their tax-payers own. And this source of wealth, prestige, and vertical mobility is also of immediate importance for the upper classes in a monarchy. https://en.wikipedia.org/wiki/Horatio_Nelson%2C_1st_Viscount...

Very few of these monarchies exist now. Many of them fell in the aftermath of WW1, and some of the big remaining ones fell in the aftermath of WW2. A positive of this is that now the remaining monarchies see war not as a means to extending their wealth, but, if on the losing side, as a means to ending them entirely. This didn't use to be the case, as previously losing monarchies might be given the opportunity to fold into the conquering monarchy as a subordinate power or noble.

[bradrn]

Deveraux explicitly endorses (1) in the article:

> If anything, I think cultural values have lagged, resulting in countries launching counter-productive wars out of cultural inertia (because it’s ‘the doing thing’ or valued in the culture) long after such wars became maladaptive. Indeed, I’d argue that’s exactly what Russia is doing right now.

[krunck]

It's what the US has been doing since WWII.

[anonymouskimmer]

In the past 30+ years the US wars (minus Afghanistan) have probably been reactive responses to the OPEC oil shock of the 70s and a bit of the US Embassy hostage situation in Iran. I wonder how much a gallon of gas costs if you factor in all of the money (not including the cost of lost lives) from those wars.