How did the French and Indian War cause the colonists to rethink their relationship with Britain?
Because of the French and Indian War, which was fought on American soil, Britain felt it was only right that the colonists foot some of the bill for the war that was fought to protect them.
Once Britain decided to impose taxes on the colonies to collect some revenue to pay the war bill, the colonists attitude toward Britain changed. They began to feel that they were being persecuted, being held responsible to pay for a war that Britain would have waged anyway, since they were fighting France for territory in North America.
Not only did the colonists resent being held financially accountable for the war, they discovered that they were competent soldiers. They had lost many men in the fight, but George Washington fought in the French and Indian War and this military service prepared him to lead the Revolution as Commander in Chief of the military.
Events during the French and Indian War and its aftermath planted the seeds for the American Revolution.
The British generals in America during the French and Indian War did not value the colonial troops who fought alongside them. After the war, the British rewarded the Native Americans who fought on their side with the Proclamation Line of 1763 while the colonists were punished by this arbitrary line that they were not allowed to cross. British officials got to see firsthand how openly the colonists flouted taxation and shipping laws and after the war they sought to make the colonists pay their fair share of the bill--after all, the British troops were stationed in America for the colonists' benefit, at least according to Parliament. The colonists felt disrespected by the taxation without their consent and openly began to consider their independence.
The French and Indian War was an expensive endeavor. The King decided to pass on the costs to the colonists, and thus an onslaught of taxes. This angered the colonists, and thus "taxation without representation" began. Basically, the argument was that the colonies had no representatives in Parliament to decide if there should be a war, and yet they were paying for it.