Millions of words, thousands of learned analyses have been written on the subject of imperialism.
But sometimes you don't need a dissertation to get to the heart of the matter. One week's news from a cruel and purposeless war tells the story.
Here's how it goes from one perspective. Joe and Jimmy grow up in an industrial district where the class vengeance of the Tories in the 1980s has swept employment and hope away, leaving shattered and semi-derelict towns and villages with shrivelled expectations and no prospects.
The great capitalist crash of 2008 snubbed out whatever recovery there may have been. So they enlist in an army which has been used time and again to try to impose the same world system which has crippled their own community on recalcitrant countries across the globe.
Poverty conscripts them to oppress the even poorer in a conflict which not even the entire spin resources of the Anglo-American PR industry can render comprehensible, let alone supportable, to the majority of the people.
What does their "humanitarian mission" achieve? It earns them the enmity of the people whose land they control without the slightest by-your-leave.
The regime they prop up presides over a heroic increase in opium production - but dances to Nato's tune.
Joe and Jimmy's mates back home, stuck in the twilight rubble of neoliberalism's "no more boom and bust," may seek a way out through heroin produced by the very warlords their schoolfriend is keeping in power.
And here's the other side. Mohammed and Maya, unlike Joe and Jimmy, stick to their own country. They wish to grow up in peace. They have the dignity of humans, but spend their childhood in a land denied the dignity of nations, the right to self-determination.
They know nothing of opium and nothing of neoliberalism. But they know that their parents and their siblings are afraid of the foreign men who come crashing through their village with guns, helmets and threats.
Mohammed and Maya are home and want it to be their own.
Joe and Jimmy should be home but have been sent to Afghanistan in the service of the same elite which has blighted their own families' lives, albeit with less bloodshed.
Joe is blown up by a roadside bomb. His grief-stricken family are offered every consolation which an unctuous and hypocritical government can muster except the words which might make a real difference - "he did not die in vain."
Because everyone now knows that with the Afghan war deep in its 11th year such a claim would be a preposterous lie.
What makes some sad makes others mad. Jimmy is enraged by his comrade's death, one among so many in a pitiless struggle in a hostile land.
The casual anti-Muslim racism he imbibed back home, and which the very fact of his presence in Afghanistan as a representative of a superior and conquering culture reinforces, inflames him still further. The "white man's burden" becomes too much to bear.
And in the dead of night he kicks in the door of Mohammed and Maya's little home. They awake in time to see their mother shot down before their eyes. Then they too are sped on their way. Martyrs. And statistics.
No Joe, no Mohammed, no Maya, and Jimmy facing a court-martial. A pitiful microcosm of a pitiless war.
But not a pointless one. They have all died so Nato's military machismo remains intact.
So that Cameron and Obama do not have to stand on the White House lawn and tell the world the truth. "We are beaten. We should never have gone there. And now we are leaving."
Because if that awful truth were to be acknowledged then the larger reality might dawn - that the "masters of the universe" are not merely greedy self-seeking bullies, but that they also have feet of clay.
Now if that idea caught hold and people acted upon it then Joe and Jimmy could live in a country which offered them fair prospects in their own neighbourhoods, rather than sending them to slaughter and be slaughtered in criminal colonial conflicts.
And Mohammed and Maya could grow up - alive, unafraid and shaping their own future.
That is the world which imperialism denies us, and that is the importance of the Stop the War Coalition's struggle against it.
I seldom wish to have been a tabloid subeditor, you may be relieved to hear, but some stories - well, you just can't help yourself.
I have fulminated previously about the way recent years have discredited the entire stupid, corrupt, dangerous but absurd elite which trades as the ruling class in this country.
From war to banking, from MPs' expenses to cozying up to Murdoch they have got everything wrong, and made themselves very rich while doing so.
It is a tale worthy of dramatic illustration.
And now we have that illustration. Only in our mind's eye so far, though don't tell me no-one took a snap at the time - David Cameron's quick canter on the horse loaned to News International's Rebekah Brooks by the always-here-to-help Metropolitan Police.
The banker's lackey atop one of the few honourable employees of Britain's biggest police force through the grace and favour of the now-dethroned governor of Rupert Murdoch's British provincial administration. What an image.
The horse, unsurprisingly, did not long survive the experience.
Denied dignity in a working life spent conveying frequently less intelligent animals around town, and maybe forced to charge the occasional demonstration, it was further spared no humiliation in retirement, being hacked around - pun intended - by a posh boy the country would like to throw at the first, if that is the correct technical term.
The knackers' yard must have come as a blessed relief to the nag.
Nevertheless the poor horse's fate is a suitable foreshadowing of the impending doom of Brooks, the bought-and-paid-for Met and Cameron, facing prison, humiliation and electoral rejection respectively. The horse hasn't bolted, so we can slam the stable door on the whole squalid crew.