The USA under the Confederation may have had the same name as the modern-day USA, but it was not the modern-day USA. The USA (Confederation) and the USA (Union, or also called "nation"), are different entities. The argument can be made that while the USA (Confederacy) was a "firm league of friendship" among a number of "free and independent states," the USA (Union) was a separate political entity that, although it replaced the USA league, was something completely different. Saying that the Articles was the first constitution of the USA, and then providing a link to the (modern-day) United States, is misleading. My point: The article as it currently stands is incorrect because it asserts that the Articles was the constitution of a union that did not yet exist, although the political body in place did have the superficial similarity of having the same name.

And the verifiable reliable sources which support my interpretation are the Declaration of Independence and the Articles of Confederation and Perpetual Union.

Perhaps I didn't express my convictions eloquently enough to be understood, since the differences are not easy to distinguish. If I'm not clear in my explanation, point to the unclear parts and ask me to reexplain.