A Constitutional Amendment is an extremely difficut process, as it should be.
==> The mood and time might be right for it however.
Yes, for now, but will the mood last. The reason the amendment process is so involved, deliberate, and drawn out is to prevent emotional responses to drive the amendment process. Similar to others, I am angry over this decision, just as is almost everyone I know. However, even though that anger may be the impetus to call for an Amendment, it is not the right frame of mind for the process.
Further, the issue, at least from perspective, is not eminent domain per se. The issue is the interpretation of 'public use'. I think it would be a mistake to try to define 'public use' in Constitutional terms.
I also think it would be impractical to restrict ED to the federal level. Asking a local or state government to seek congressional action every time they want to build a new hightway, or widen a two-land road to a four-lane road doesn't stike me as practical. I also fear it would open Pandora's box for pork barrel negotiations and compromise. Perhaps that example illustrates why the issue is not eminent domain, but rather, it's the interpretation of public use.
Good Luck
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As a circle of light increases so does the circumference of darkness around it. - Albert Einstein