Yes they were.
Well, after you left the Empire and went your own sweet way, we did quite well without your help ... reluctant and tardy though it was, and are still doing reasonably well for a nation the size of Kentucky and the population of California and Texas. So come back if you want to: there's always a welcome for the prodigal son.
However, I doubt many Americans could stomach the tolerant, socially aware lifestyle that prevails in European and Commonwealth nations and it would rebel once again ... I hope not by provoking another world war like it did the first time.
We obtained the colonies by conquest and settlement. Not necessarily noble means of acquisition, but far better than stealing from one's own compatriots: that's treachery.
As for taxation in return for representation, that was mere posturing: (a) you could have had it if you really wanted it; (b) America was already becoming more and more republican in response to the belief that Britain was a den of iniquity and that the only way to prevent the disease from infecting the colonies was to secede; (c) it preferred to trade with the enemy; (d) it wanted to occupy more and more Indian or French territory, despite British Treaties recognising the rights of the Indians/French ...
A beautiful, adaptable, versatile document can still be fundamentally flawed if its provisions are found wanting ...
You final statement reeks of the rantings of the radical right, which does not represent the People at all, but simply a vocal minority paranoid at the prospect of a legally constituted government actually taking its role and responsibilities seriously.