The “something” in the first line of Frost’s “Mending Wall” is the physical world. To be specific, it’s a phenomenon that shares the poet’s name: frost heaving. A native San Franciscan like me, Frost would have seen frost heaving in effect only after he moved to New England with his parents. When land freezes, it expands, causing upward pressure on the surface. In the spring, the surface shifts again as the earth thaws. Asphalt cracks, and man-made structures can shift and be damaged.

When the speaker of the poem and his neighbor meet to repair the stone wall that divides their properties from one another, they follow a rigid custom. If a stone falls on the speaker’s side, he replaces it in the wall; the same applies to the neighbor. Because the entire wall, including the stones that did not fall to the ground, shifted when the earth froze and thawed, replacing the stones is not an easy task. The gap where each stone used to be is no longer there. The speaker recognizes the futility of the exercise, remarking that “We have to use a spell to make them balance: / ‘Stay where you are until our backs are turned!’” (18-19) and speaker calling this ritual “just another kind of outdoor game, / One on a side” (21-22), aligning it with baseball, football, and other games that are meant to be friendly but so often seem more like a form of warfare.

The neighbor sees the replacement of the stones as a rigid duty. When the speaker points out that neither he nor his neighbor has animals that might wander (“He is all pine and I am apple orchard” [24]), the narrator reasserts his refrain – one of the most well-known lines in American poetry – “Good fences make good neighbors” (27). The line “Spring is the mischief in me” (28) suggests the narrator’s desire to mimic the thawing earth by upsetting the foundations of his neighbor’s thinking – his neighbor whom he later calls “an old-stone savage armed” (40) and intimates that “he moves in darkness as it seems to me, /Not of woods only and the shade of trees” (41-42; Hint: want to emphasize something? Make it rhyme!).

In this poem, the neighbor’s very human desire to divide the world between “mine” and “theirs” runs counter to the earth’s annual disruption of man-made boundaries. The very fact that the speaker participates in this annual ritual with his neighbor shows that on some level he respects it. He likely grew up seeing men repair stone walls in this way, and his objections are gentle, fanciful, and mostly unvoiced. All of us, on some level, have an inherent fear of barbarians at the gate. I grew up a compulsive door locker: guests who leave my house – even my closest friends – haven’t even left the porch before they hear the deadbolt snap into place behind them. Others live in houses placed far back from main roads, behind privacy fences or hedgerows or locked gates. Some install alarm systems. Some own large dogs. Some worship the second amendment.

But the narrator’s question for his neighbor is key: “Why do they make good neighbors? Isn’t it / Where there are cows? But here there are no cows. / Before I built a wall I’d ask to know / What I was walling in or walling out, / And to whom I was like to give offense” (30-34). The speaker is not saying that unthinking loyalty to tradition is dangerous – though it can be, and the poem does beg that question. What these lines do instead is assert our identity as rational animals. We are not “old-stone savages” armed with rocks, nor are we wandering cows liable to eat other people’s apples. We can engineer our environment – as in the building of fences and walls – but we can also contemplate the consequences of our actions. We can be silly, offering “elves” (36) as a possible reason for the tumbling down of rock walls. We can be stubborn, like the neighbor, but we can also choose to be passive and let natural forces do what they may. We can be compassionate, as the narrator suggests he wants to be – though the suggestion is very much in the subjunctive, as if he lacks the guts. We can abandon outdated ways of thinking and living. We can contemplate the nature of the “something” deep in the earth that seems determined to – gently, patiently – grind our walls and distinctions to dust.

Consider this: in North America, the boundaries of our nations and of many U.S. states have their origins in the original borders put in place by the Europeans who colonized this continent beginning in the early sixteenth century. Florida was Spanish territory; Louisiana was Spanish too until it was ceded to the French. Canada was French until 1763, as were large swaths of the northern Midwest. Our current border with Mexico is only the latest iteration of the boundary between “New Spain” – which at one time included Texas, New Mexico, Arizona, and California – and the United States of America. Even Russia played along, staking a claim in Alaska and even establishing a little pied-à-terre in northern California.

All the nations that created colonies in North America were also fighting one another in Europe. The descendants of the barbarians that once sacked Rome lined up massive armies on the fields of France, Germany, Spain, the Netherlands, and England. They fought over many things, but in the years most associated with the colonizing of North America (let’s say 1550-1763), they mostly fought about religion. The borders of these nations shifted after each war, with slivers of territory changing hands, and when individuals, families, and, in a few cases, entire religious sects found themselves without safe homes, many left Europe to go overseas, where in most cases they found enough empty land that they could (temporarily) stop fighting about religion. Think the Puritans are assholes? Go to New York. French too Catholic for you? Go south. The land itself, which seemed limitless at first, became the primary object up for dispute. The French lost Canada to the British in 1763. The British lost its American colonies in 1783. The United States bought Louisiana and much of the Midwest and northwest from France in 1803. After a series of skirmishes and one big war, Mexico retreated to its current border in 1848, leaving behind thousands of Spanish speakers who never stopped speaking its language, eating its food, and practicing its traditions.

The Europeans kept fighting, for a while. France tore itself into pieces after its revolution, then united under Napoleon and turned its ire outwards. Traumatized, the continent quieted down for a while. Then the German states united under Bismarck, the Italian states under Garibaldi. The British held on to their Indian and South African colonies with  teeth and nails, while fighting the Russians in the Crimea and the Irish on their own borders. Archduke Franz Ferdinand was assassinated in Sarajevo, kicking off the event that most historians now agree was hardly the first world war. Punitive tactics in the Treaty of Versailles and a worldwide economic depression made the next war all but inevitable. Europe was divided in two by walls and tanks and guns and conflicting ideologies. Even when I went to elementary school in the 1980’s, history was the study of warfare and borders. North and South Korea; North and South Vietnam. Estonia, Latvia, Lithuania. The R.S.F.S.R. I learned all the SSR’s by heart in seventh grade; the next year the Berlin Wall was down and there were new boundaries to memorize.

But then something happened: it got better. Germany reunited without aggression. France and Britain put aside their ancient differences. England slowly learned to live at peace with Ireland. I know I picked a bad week to hold contemporary Europe up as a model of utopian living, and I know that its openness to Syrian immigrants is the source of serious dissent. But the system works. Wealthier nations in the EU bolster struggling ones, just as the wealthier southern states funded industry in the north in the years immediately after the American Revolution, when the new nation was bankrupt. Its healthcare systems – some but not all what we would call “socialist” – function efficiently. Its governments cooperate. Its nations trade freely. Even after the attacks in Belgium this week and in France in November, when many Americans cancelled their plans to vacation in Europe, the French and Belgian police, military, and intelligence services sprang into action to detect and stop active terror cells. All human communities are marked by violence. 21^st-century Europe – though its history is hardly fully written – does as good a job at cooperating and stemming violence than any community I know of in history, and a better one than most.

So here’s my question. Why is it that Europeans cross borders passport-free while we still dicker over borders that their ancestors left behind centuries ago? Europeans made progress (or, more accurately, had progress beaten into them by a century of horror); we lag behind. We cling to old borders. We treat their enforcement as a sacred tradition. We parrot statements we’ve heard others made – statements more inflammatory than “Good fences make good neighbors” and a lot less euphemistic. We talk about drugs and guns and disease and rapists – all of which we have in this country, in spades, already. We rant about barbarians at the gate when, in this context, we are the old-stone savage armed.

It’s Easter. The sun is shining. Spring is the mischief in me.