We the People of the United States, in Order to form a more perfect Union, establish Justice, insure domestic Tranquility, provide for the common defense, promote the general Welfare, and secure the Blessings of Liberty to ourselves and our Posterity, do ordain and establish this Constitution for the United States of America.
This one sentence pretty much makes your point concerning perpetual Union. The key phrase here is "a more perfect Union." The Union itself is taken for granted -- the Constitution is meant only to improve it.
So what about the nature of that Union? Let's now pass over to Federalist #40, which is basically an argument justifying the replacement of the Articles of Confederation.
One resolution goes as follows: The recommendatory act of Congress is in the words following: "Whereas, there is provision in the articles of Confederation and perpetual Union, for making alterations therein, by the assent of a Congress of the United States, and of the legislatures of the several States; and whereas experience hath evinced, that there are defects in the present Confederation; as a mean to remedy which, several of the States, and particularly the State of New York, by express instructions to their delegates in Congress, have suggested a convention for the purposes expressed in the following resolution; and such convention appearing to be the most probable mean of establishing in these States a firm national government
IOW, the Union that the Constitution was created to improve upon The Articles of Confederation, which is self-described as "Articles of Confederation and perpetual Union."
The conclusion is quite obvious. The Constitution was trying to perfect a Union that had already been codified as "Perpetual."
... Not that I expect even such an obvious thing to carry any weight with the master debaters on the other side.
take out the "de" and what do you have?
Can you tell I was in the military?
Walt