Yes, truly without having first being British colonies, the United States, India and Ireland would have been unable to stand on their own feet and peaceful transitions they were too. Quite right!
Ireland was not colonised. That was an old fashioned European land war.
India had a relatively peaceful transition, considering what it could have become.
You are probably ignoring the Hindu-Muslim riots that took place during partition and the immediate Indo-Pak war after that. These were a result of the british policies.
Ireland's was the first colony, it's a matter of record and to this day protestant settlers descendants inhabit the north of the country. [1]
India's transition was not peaceful.
[1] https://encrypted.google.com/search?hl=en&q=the first colony