America has few valuable resources in 1776. It's only cash crop was tobacco which was child's play compared to the wealth generated by growing sugar in the Caribbean. No-one understood the importance of oil until about 1917 at which point it was quite significantly too late. Coal only became important in the 1800s. Other than that the 13 colonies did not have much else.

treated the American English citizens like they were beneath them.

This is something of a myth that most American's seem to fall for. Gordon Wood's book "The Radicalism of the American Revolution" is useful to quote:

"The social conditions that generally are supposed to lie behind all revolutions—poverty and economic deprivation—were not present in colonial America. There should no longer be any doubt about it: the white American colonists were not an oppressed people; they had no crushing imperial chains to throw off".

Americans were taxed at a much much lower rate than Brits (most of whom were not represented in Parliament either) - around 26 times less to be specific. At page 85 of his book "Empire", Niall Ferguson points out that ‘New Englanders were about the wealthiest people in the world’ at the outbreak of the War of Independence and (within the Empire) ‘the [people] who revolted against British rule were the best-off of all Britain’s colonial subjects’.

The reason taxes were raised on the US colonies was because after spending huge amounts of cash protecting the colonies from French attacks in the Seven Years War (called the French Indian War in the US) the British government faced an increase of about 56% in the national debt to £132.6 million which given Britain's GDP at the time which was £84.3 million represented an debt/GDP ratio of 157%, about equivalent to the position of Greece in 2012 after the financial crisis. In order to increase tax revenue from the colonies they passed various laws, some creating in America taxes that were common in England but previously avoided in America to stimulate growth. Others, like the Tea Act, lowered the duties to combat and undercut smugglers. The smugglers didn't take kindly to the officials trying to undercut their criminal operations and chucked a bunch of tea into Boston habour. The Boston Tea party had nothing to do with oppressed colonists - Benjamin Franklin suggested the smugglers pay compensation for the criminal damage when he wrote in a letter to Samuel Adams and John Hancock (who was a prominent smuggler):

I cannot but wish & hope that before any compulsive Measures are thought of here, our General court will have shewn a Disposition to repair the Damage and make Compensation to the Company.

The truth is quite the opposite to what you say. The British government had avoided taxing or being too bureaucratic in the US in order to help the colonies grow. When the time came for the now very wealthy Americans to start paying their taxes to fund just a small percentage of their own defence costs they refused because they did not recognise Britain's authority to levy internal taxes on them (like it did over every single other of it's citizens). Britain had never given up this right but had chosen not to enforce it - Howard Temperley calls it "Imperial inertia" in his book "Britain and America Since Independence". There was no oppression, no crushing burden or authoritarian crackdowns or at least nothing unusual inside or outside of Britain and it's ridiculous to say that by asking Americans to pay just a fraction of what the average Brit was paying at the time in taxes (to fund wars protecting the American colonies) the government was somehow treating the colonists as second class citizens.

The reality was that the American colonists never really saw themselves as a colony; they saw themselves as another country entirely from the start or at least as an equally powerful mutation of Britain. It doesn't take a genius to work out that if you try and establish your own authority apart from the people who you previously owed allegiance to there's going to be conflict but it took until 1763-1776 for that disagreement to become visible because British-American government has been so limited beforehand.