… (For example) the hard power of military force. In recent weeks, we have seen Western governments struggle to come up with a strategy to contain ISIS, and forced to watch helplessly as hostages are beheaded. A decade of intervention (and billions of spending) leave Iraq and Afghanistan no more stable than before; Libya is less stable; there are regular atrocities in Nigeria; and so on.

The hard power of the West means that few countries would be foolish enough to put an army or navy into the field against it. But they don’t need to do that to cause massive disruption; the West is vulnerable at a million points because of its open model and worldwide network.

The example that springs to mind …  is The Eagle of the Ninth, a rattling good yarn by Rosemary Sutcliff based on the story of the Roman ninth legion which (on some accounts) vanished in the wilds of Scotland. In the book and film (The Eagle), the soldiers are swallowed up in the mists, and picked off by local tribes. …

In other words, conquest of territory is one thing; holding that territory is quite another, in the face of the hostility of the local population. Perhaps the only “successful” approach is the ruthlessness of Genghis Khan—wiping out or enslaving the men and women—and that is rightly not an option.

So does all this matter to the global economy, or are the markets right to shrug their shoulders, and treat terrorism and rebellions as background noise? I think it does matter for a couple of reasons. For a start, economic globalisation depends on the different power blocs agreeing to co-operate in order to smooth the flow of trade and investment. But the example of Russia and Ukraine shows that co-operation can break down and Japan/China tensions may cause something similar.

Secondly, this powerlessness adds to voter dissatisfaction. I’ve dubbed this the “Starbucks problem” —people get their coffee exactly the way they want it, with soy milk, wet or dry etc—and they expect politics to be the same way. But you could also dub this the Hollywood problem. We are used to seeing Spiderman or Bruce Willis save the day and the enemies being soundly defeated. But real life is not like that.

Our elected leaders are dogged by Monday-morning quarterbacking as pundits and rivals declare that if only they had been tougher (or only if they had not been involved in the first place) said disaster would not have happened. If only we had bombed Syria in 2013, things would be better—maybe, but maybe ISIS would now be in charge in Damascus. Again, this voter dis-satisfaction may lead to electoral success for those who have simplistic solutions (blame the foreigners, blame the minorities at home) and this will only make matters worse. And then the markets will really have something to worry about.