#1. You are the one that used Rome's subjugation and brutal treatment of ethnic people within its boarders. How is using the native Americans a red herring? Because they didn't produce goods? Because they were savages? So, by your requirements the Portuguese couldn't count Brazil as part of its empire? How about the African lands that the Brits fought savage tribes for?
I do see your point. However, I believe there is a difference. Sadly, the Africans were far more advanced than the natives in North America. The Africans were iron age people; the Indians were of the stone age. The Africans produced goods. They traded with other Africans. The Africans had lands and territories. The lands of the Africans were seized by force or subterfuge and were exploited. Africa was populated too. While all of this seems similar, it is but it isn't. Most of the Indians had no real lands nor claims to the lands. There were so few of the Indians; Americans far outnumbered them. Vast and I mean vast tracts of land were not inhabited, i.e. mostly all of the continental U.S. Most land was not seized. Most all lands were not obtained through subterfuge. It was not necessary. Most Indian tribes never fought the US government. Americans just moved into vacant land. Most settled peacefully and made treaties. Some chose the wrong sides in fights wars between European powers and wars Americans fought against the British. That wasn't conquest; they chose the losing side. There were tribes we fought. They were few in number. Some might argue that the natural resources were plundered. They really weren't. The natural resources were utilized and the wealth created remained. The US expansion westward was more of a natural progression like any other expansion of peoples throughout history. The Indians ended up adopting the ways of the Americans and have had to make a concerted effort to maintain any vestiges of their heritage.
Now compare that with what your examples of true empire. The Romans, Portuguese, Brits, Spanish, etc. These people conquered other nations with real societies. They subjugated the people. They raped their natural resources and plundered their wealth., The plundered wealth was sent back to the home country of conquerors, not benefiting the locals one bit. For those societies that were less civilized, they enslaved the local populations, or in the case of the Romans enslaved civilized peoples too. They forced them into labor. The conquerors taxed them and otherwise dominated them. The conquerors were few in number compared to the population they controlled. The culture of the conquerors never became the prevailing culture; at least until a sufficient number of the natives were exterminated, which happened in many instances.
#2. I know there is no single western European culture. That was my point. Other than the federal government, holidays, and the shows we watch on tv, I find myself wondering what culture someone from, let's say, southern Arizona shares with someone from deep in the bayous of Louisiana, or the woods of Maine.
Your point was that Western Europe was not a single culture? That's not how it read. I'll take it as that if you say that was your intent.
Those things you mentioned such as government, holidays, TV, etc. all make a culture plus many more. Americans of all races from all places share much more in common than you realize. You don't have many foreign friends or socialize in foreign circles, do you? If you did, you would understand how much more the people from diverse regions of the US have in common than we do with closely related societies such as those from Western Europe.
#3. The biggest problem I have with conversations about "the civil war" is that we constantly refer to it as a civil war. It was not a fight within one country to change it or overtake it's government. It was a war between two different countries. The confederate states had a union of their own, a constitution, a president, etc., etc.. So our civil war was no more a civil war than was our revolutionary war. Same thing happened. The colonies told the government that they previously belonged to to kick rocks, and the big government waged war in an attempt to bring the upstarts back under their control. The only real differences between the two were which side won, and that the colonists waited until after the war to draft a constitution and elect a president. So really, in some ways our revolutionary war was closer to being a civil war than the war between the states was.
This is patently false. The U.S. was one country. It fought a civil war. By any historical account or definition, it was a civil war.
In a free society, it is not the obligation of the citizen to prove to the government that he is a good person. It is the obligation of the government to prove to the rest of the citizenry that the citizen is a bad person, with probable cause.