Take a careful look at Justice O'Connor's dissent on page 803. She thinks Berman and Midkiff are correct, but Kelo is wrong because it is distinguishable from those "public use equals public purpose" cases. How does she distinguish them?
"The Court’s holdings in Berman and Midkiff were true to the principle underlying the Public Use Clause. In both those cases, the extraordinary, precondemnation use of the targeted property inflicted affirmative harm on society—in Berman through blight resulting from extreme poverty and in Midkiff through oligopoly resulting from extreme wealth. And in both cases, the relevant legislative body had found that eliminating the existing property use was necessary to remedy the harm...Thus a public purpose was realized when the harmful use was eliminated. Because each taking directly achieved a public benefit, it did not matter that the property was turned over to private use. Here, in
contrast, New London does not claim that Susette Kelo’s and Wilhelmina Dery’s well-maintained homes are the source of any social harm. Indeed, it could not so claim without adopting the absurd argument that any single-family home that might be razed to make way for an apartment building, or
any church that might be replaced with a retail store, or any small business that might be more lucrative if it were instead part of a national franchise, is inherently harmful to society and thus within the government’s power to condemn."
Do you find this persuasive? Does this have any relevance to the textual language limiting takings of private property to "public use?" If public use means public purpose and public purpose means anything advancing general welfare, is O'Connor's attempt to distinguish Berman and Midkiff persuasive? If Ms. Kelo's well-maintained home stood in the path of mitigating New London's severe economic distress, why isn't this a sufficient public purpose for the taking?
If the Constitution can mean anything the Court wants it to mean, the Court can hold that some public purposes are more equal than other public purposes.
I do like O'Connor's Madison quotation on p. 805: "[T]hat alone is a just government which impartially secures to every man whatever is his own."
