A map has circulated showing the Islamic State's five-year plan: a caliphate that stretches from the Iberian peninsula to western China, including all of India, north Africa, the Middle East, Asia Minor, and southeastern Europe. It's an ambitious agenda. According to an Islamic State spokesman, the map doesn't show lands to be captured but, rather, lands to be liberated: "We will die for [the caliphate] until we open those occupied lands from Jakarta to Andalusia." Andalusia's a big deal to Islamists, who see it as their high-water mark. "Spain is the land of our ancestors and we will open it with the power of Allah." This is a good time, then, to talk about a touchy subject: empires and occupation. Nothing angers an Islamist like an infidel occupying Muslim land. The political Left has a taboo along the same lines; no memory is reviled like those of the old empires. In some ways, the anti-imperialists are right -- historically, empires have been a hit-or-miss proposition. The British Empire built roads and schools, the Roman Empire built roads and baths and murdered a great many people, the Mongol Empire murdered a great many people and built a pyramid using 90,000 of their heads. But whether or not empires deserve the hatred that has been heaped on them since World War II, they're mostly a thing of the past. The Mongols rule only Mongolia, the Romans have melted into a nation of well-dressed womanizers, and the sun sets on Britain every day. With the Soviet Union gone for 20 years now, there's really just one great empire left: the Arab Empire. The Arab League covers 5 million square miles, stretching from the Persian Gulf to Africa's west coast. When people think of indigenous peoples of the Middle East, they think of Arabs -- but in the grand scheme, the Arabs are new to most of the territory they control. Striking out from the Arabian Peninsula around 600 a.d. with their new Muslim message, they conquered, converted, and murdered their way into ethnic dominance from Iraq to Morocco. Today's Egyptians are not descendants of the Egyptians who built the pyramids -- though the bitterly oppressed Copts might be. Moab and the Moabites have disappeared, the Lebanese of antiquity were Phoenician, the Philistines were not Palestinian. In fact, only one nation west of Persia weathered the storm of Arab expansion and reestablished self-governance: the Judeans. For 3,000 years, there have always been Jews in Israel. They were conquered by the Assyrians, and the Babylonians, and the Greeks, and the Romans, but through the massacres and mass deportations, a few Jews always remained. In 1948, the United Nations voted to acknowledge a renewed Jewish homeland in Israel, and the surrounding Arabs vowed to drive the Jews into the sea. The Jews survived, and recovered more of their pre-Diaspora territory than the U.N. intended -- but the heartland of the ancient Jewish kingdoms, the Judean hills on the River Jordan's west bank, remained in Arab control till 1967. In '67, an Arab coalition attacked Israel, and the Jews got some more of their homeland back. Sort of. Ever since, the territory has had a split personality. Israel has the final governing say, but the local administration is mostly Arab. A majority of the residents are Arab, but there are large, thriving Jewish communities. The "occupied territories" are occupied by someone; the question is, by whom? And the answer is: By Arabs, obviously. That's not to say people don't have a right to land they own and were born on; perhaps there's nothing wrong with the Arabs having a de facto empire -- but it's silly to pretend they don't. As silly as if the British pretended they were indigenous to South Africa and refused to acknowledge the legitimacy of black citizens. Now, per its map, the Islamic State wants to replace the Arab Empire with an even more ambitious Muslim one; in the Hamas spirit, it wants to end the Spanish occupation of Spain and the Indian occupation of India. We know that imperialism is a flashpoint for young radicals -- how many times have we seen #freeGaza and #freePalestine over the last two months? So the question arises, will the anti-imperialists take the same view of removing the Hindus from Hindustan that they do of removing the Jews from Judea? Let's hope not. There's another point here, as a postscript: There is some good news for both lefties and righties who genuinely abhor the domination of one nation by another. The Kurds, another ethnic group long subjugated by Arab neighbors, have taken up arms against the Islamic State -- and they may come out of the fight in better shape than they went in: with a renewed homeland of their own. Unfortunately, the arms they've taken up are mostly Soviet relics; the Islamic State, meanwhile, has top-shelf American stuff. When Israel was fighting for its life in '48, its friends and sympathizers helped it get the guns and ammo it needed. Israel should extend the same courtesy to its Muslim cousin, Kurdistan. By the same token, when the United States decided to throw off its own yoke of imperialism and fight for independence from the British, the French came to our aid. I don't mean to diminish France's contribution to our revolution, but they were motivated, in part, by the maxim that the enemy of your enemy is your friend. If the United States isn't inclined to help the Kurds because it's the right thing to do, we ought to take a hard look at that Islamic State map, and help them because it's the smart thing to do.