After the American's success in the French and Indian War in 1763, the Colonists were still celebrating while the British were still in debt from the war. The British were the ones that had aided the Colonists in winning the war, and the American Colonists still had not helped the British pay off their debt. Because the British had sacrificed so much for the war, the British had an automatic IOU card that they were using when they decided to put different acts into motion.
As Britain is the mother country, and they had helped the Americans win the war, they rightfully decided to tax the Americans with Acts such as The Sugar Act, The Currency Act - which prohibited American colonies from making and distributing their own currency, The Stamp Act - which made it so that you had to have a stamp on any kind of paper to make it legal, and many more acts that were justified to help pay off the British debt because of the money they spent on the American Colonists.
The new acts that the British put into motion to help reclaim their debt Amazingly, made the American Colonists angry. Even though the British had every right (Because they were the mother country) to impose these new acts upon the American Colonists, and they had proper justification (They helped pay for the war) somehow, the Colonists would not agree to pay a small tax on some of their everyday use items. It could be argued that the Colonists were justified in waging war and breaking away from Britain, but evidence concludes that this statement is wrong, as the British were fair, and did not tax as many things as they could have.
As the colonist's anger increases, new groups such as The Sons of Liberty, and The Daughters of Liberty were formed (these groups influenced most of the other Colonists) to help rile up the American Colonists, which eventually led to America breaking away from Britain. Another Reason that the Colonists were not justified in waging war and breaking away from Britain, is that they were a colony. This means that the entire point of their existence is to supply raw materials and profit to the mother country.
In conclusion, the American Colonists were not justified at all in waging war and breaking away from Britain, because of all of the help and effort Britain put into protecting and keeping the colony out of harm's way. The American colony was not justified to wage war for another reason as well, and that is because they only existed because the British protected them in the first place and they are even a colony, which means that they need to supply materials and profit to their mother country to help it flourish and bloom to make it more successful.