You could point at many different moments in history and declare them to be the spark that eventually kindled into the modern world.

But one of the more convincing of these arguments posits that it was the development and deployment

of state sovereignty, often called Westphalian sovereignty, that shaped the modern geopolitical landscape

because of how it helped define the outlines, in a literal sense, of the modern

nation state. In essence, Westphalian sovereignty says that every country has authority over what

happens within its own borders, so the U.S. government decides and manages what happens within

U.S. borders. France controls their stuff. Nigeria decides what happens within Nigeria and so on.

This concept, though seemingly obvious to the point of being the default assumption today, wasn't so obvious or baseline back in the mid-17th century, when it emerged from the peace of Westphalia, which brought both the 30 and 80 years wars to an end in Europe.

And it still wasn't obvious when this concept was further refined in the 18th century

to include more detailed assumptions about non-interference.

Basically, to what degree can governments meddle in their neighbor's business?

And initially, the conclusion was that they shouldn't interfere at all.

But in the 19th and 20th centuries, especially following the First and Second World Wars, this concept was adjusted a bit,

as it became clear that if you're completely non-interventionist, things like the Kaiser and Hitler happen, and that can then create a sort of vortex that pulls everyone else into conflict, whether they want to be involved or not.

Not intervening in some cases can result in the upending of an otherwise stable order that allows governments to exist alongside each other without getting up in each other's business most of the time.

The modern international system is predicated consequently on generally leaving each other alone,

but also a mesh of interconnections between governments that allows them to do business with each other, create treaties and other relationships,

while also criticizing, punishing, and otherwise hating upon their enemies, all without most of the time going to war.

As a result of our long history of violence, followed by a period of global warfare

in the establishment of systems that allow us to deal with each other without going to war,

the past three decades or so have been, by most metrics, the most peaceful in all of recorded

human history. Now, this claim, to some, will sound ridiculous. There is war, there is conflict and strife and terrorism and abuse and all sorts of other large-scale violence

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