In fact, the beginning of the war was mobile and extremely bloody, as were the last few months, when the big offensives of 1918 broke the German Army. The rate of killing in the muck and mud of the trenches was much lower than during the mobile part of the war.

If the inheritance is mixed, the war still casts a long shadow, refracted through what can now seem the inevitability of World War II and our tumultuous modern history. This is also, after all, the 75th anniversary of the start of that war and the 25th anniversary of the collapse of the Berlin Wall.

The end of the Cold War was in a sense a return to the end of World War I, restoring sovereignty to the countries of Eastern Europe, one reason they are so eager to defend it now.

Analysts wonder if the period of American and European supremacy itself is fading, given the rise of China and the return of traditional nationalism, not just in Russia but in the many euroskeptic voters in France, Britain and Denmark.

Inevitably, analogies are drawn. Some analysts compare Germany after the war to Russia now, arguing that just as Germany rejected the “Carthaginian peace” at the end of World War I, so Russia is now rejecting the “settlement” of the Cold War, seeing it as unjust, chafing over its defeat and prompting a new Russian aggressiveness and irredentism.

Some question whether the lessons of 1914 or of 1939 are more valid today. Do we heed only the lessons of 1939, when restraint was costly, and miss the lessons of 1914, when restraint could have avoided the war?

Some see a continuing struggle between Germany and Russia for mastery of Europe, a struggle that marked both world wars and continues today, and not just in Ukraine, where a century ago its people fought on both sides. Others see World War I, at least as it began in Sarajevo, as the third Balkan War, while the post-Cold War collapse of Yugoslavia and its multinational, multicultural, multireligious model continues to present unresolved difficulties for Europe, in Bosnia, Kosovo and beyond. Similar tensions persist in Northern Ireland, the rump of Ireland’s incomplete revolution that began with the Easter Rising of 1916.