During World War I a small band of Irish nationalists launched a rebellion against British rule, announcing that 'England's difficulty is Ireland's opportunity' - that the calamity of British losses against Germany should be seen as a chance for Ireland to seize independence here.
I'm not a historian so readers can correct me if I'm wrong, but that seems to be a pretty common trend throughout history: as one country experiences disaster, another takes advantage to grab power. Mike Duncan's The History of Rome podcast repeatedly refers to Romans taking advantage of Persian civil wars to invade, or Goths, Persians and Saxons leaping at Roman unrest to loot a few cities.
Now Greece is facing some serious economic problems, compounded by occasional bouts of unrest and deep political divides.
Ripe for invasion! Yet of course nobody invades. Greece has had pretty poor relations with Turkey for a long time, and Macedonia, but in all the alarmed articles I've seen about Greece's predicament, none have predicted war.
Why not? Well Greece and Turkey are NATO members and Greece is an EU member. Picking a fight with Greece would probably stir up the wrath of NATO. Apart from that, though, it surely shows how far most countries have come from war that this hasn't even seemed a possibility. Greece may be less stable than some other European countries but there isn't - that I know of - a whisper of suggestion that anyone take advantage of their troubles with invasion. The idea of just raiding another country to grab loot is today considered unthinkable for most people.
It wasn't always so. A few days ago I prompted incredulity on a friend's Facebook comments when I repeated Steven Pinker's claim that now is the most peaceful time in human history. One person demanded to know why military expenditure was rising if today is peaceful. I'm not sure how expenditure levels really are, but if they are rising there are a bunch of ways to interpret it that hardly challenge Pinker's claim. (For example, maybe modern life is more peaceful because countries spend more on defence, disincentivising invasion? Or perhaps rising military expenditure is just an indicator of rising wealth generally.) I have little doubt that I in Ireland live in an era in which war is greatly delegitimised as a political tool, and that this is true to some extent even in much less stable regions, like the Middle Eastern countries that don't invade troubled Greece. Iceland, Ireland, Greece, Portugal - all have faced traumatic economic challenges, none have faced the slightest threat of conquest.