Article I.
The states said (New Hampshire, Massachusetts Bay, Rhode Island, Providence Plantations, Connection, Delaware, Pennsylvania, Maryland, New York, New Jersey, Virginia, North Carolina, South Carolina, and Georgia) hereby severally enter into a firm league of friendship with each other, for their common defense, the security of the liberties, their mutual and general welfare, binding themselves to assist each other, against all forced offered to, or attacks made upon them, or any of them, on account of religion, sovereignty, trade, or any other pretense whatever.
In my interpretation, this document is saying how the thirteen colonies need to have a close knit relationship with each other. They are supposed to get along with each other for each others sake. The states can protect one another in case anything were to happen with a foreign enemy. Its also said that it doesn't matter the argument could be about religion, what's being traded or anything else, they need to stuck to each other and fight as one.
Article XI.
Canada acceding to this confederation, and joining in the measures of the United States, shall be admitted into, and entitle to all the advantages of this union but no other colony shall be admitted into the same, unless such admission be agreed to by nine states.
Here, it says that the nation of Canada is also accepted and included in the US forces. Canada will have all the advantages that the states have and is obviously expected to contribute protection. Unless nine out of the thirteen states are apposed of it.
