The Constitution is "the supreme law of the land."
And the government under the Constitution -is- perpetual. At least, that is what Robert E. Lee said:
"The framers of our Constitution never exhausted so much labor, wisdom and forebearance in its formation, and surrounded it with so many guards and securities, if it was to be broken by every member of the Confederacy at will. It was intended for 'perpetual union' so expressed in the preamble, and for the establishment of a government, not a compact, which can only be dissolved by revolution, or the consent of all the people in convention assembled. It is idle to talk of secession."
Robert E. Lee, January 23, 1861
Walt
Unfortunately Lee was referring to the Articles, not the Constitution.