A voluntary exchange of goods or services for money is not a tax or tribute.

I already explained _hours_ ago that I was using the term American Empire semi-rhetorically. It does not matter if you show that the way the US has employed and distributed its power historically do not meet your strict definition of how an empire operates because I'm not cutting my cloth to suit the tailoring of your definition. By many accounts the neo-colonial way in which the US has conducted and continues to conduct itself is imperial.

It's kind of like duck-typing I figure. If it looks like an empire and behaves like an empire it's probably an empire.

The four behavioral characteristics that clinch it for me are: [1] the continued unilateral interference in the sovereignty of other nations either covertly or overtly; [2] the non-participation in international norms; [3] the continued garrisoning of territories in other nations; [4] the historic and current role of the dollar and the US-backed financial systems and institutions globally.

[1] https://en.wikipedia.org/wiki/United_States_involvement_in_r...

[2] https://en.wikipedia.org/wiki/List_of_treaties_unsigned_or_u...

[3] https://en.wikipedia.org/wiki/List_of_United_States_military...

[4] https://en.wikipedia.org/wiki/Reserve_currency#United_States...

When we invade countries and depose leaders who threaten to trade oil on something other than the dollar, it's not exactly voluntary.

While I disagree with the comment you are replying to, your comment isn't correct either.

There is a non-trivial amount of oil traded in the euro, and also see [1], [2]

[1] https://en.wikipedia.org/wiki/Iranian_oil_bourse

[2] http://www.nytimes.com/2008/02/25/business/worldbusiness/25i...