Virginia, Massachusetts, Rhode Island, Connecticut, New Hampshire, New York, New Jersey, Pennsylvania, Delaware, Maryland, North Carolina, South Carolina, and Georgia.
Yes, more allies means you have more backup
Also, if you have a lot of allies, everybody can help each other in their time of need (for example, NATO) and the enemies will not be as aggressive in trying to attack you
hope this helps
they found a route that took them straight to the pacific ocean!