This may seem like a silly question, but I only ask because of a U.S. Supreme Court case that actually cited the Articles of Confederation.
After the civil war, there is this case called Texas_v._White, which in the process of judging the case, the Supreme Court had to give an opinion on whether the state of Texas actually legally left the United States during the civil war. The answer was of course no. Chief justice Salmon P. Chase ruled that Texas never legally left the Union.
The interesting part is the reasons he used to justify his opinion. This is important because he acknowledged that the State of Texas and its people had officially voted to leave the Union, but even this process was void because:
"The Union of the States never was a purely artificial and arbitrary relation. It began among the Colonies, and grew out of common origin, mutual sympathies, kindred principles, similar interests, and geographical relations. It was confirmed and strengthened by the necessities of war, and received definite form and character and sanction from the Articles of Confederation. By these, the Union was solemnly declared to 'be perpetual.' And when these Articles were found to be inadequate to the exigencies of the country, the Constitution was ordained 'to form a more perfect Union.' It is difficult to convey the idea of indissoluble unity more clearly than by these words. What can be indissoluble if a perpetual Union, made more perfect, is not?"
A simple search will show that the phase "perpetual union" is not in the Constitution anywhere but all over the place in the Articles of Confederation. This suggests that Chase believed that the Union established by the Constitution is only a refinement of the Union previously established by Articles of Confederation. For matters where the Constitution does not clearly redefine (such as whether the Union is perpetual), the Articles of Confederation retains its legal authority.
Considering that U.S court cases set precedences, the case of Texas vs white seems to suggest that the Articles of Confederation still as legal power today, as long as it does not conflict with the constitution.
Doesn't that sound a little weird?