Michael Zeldin:

On a related point, Mrs. Clinton has been arguing to primary voters that she is more electable than Barack Obama because "she has been vetted fully so there will be no general election surprises." Well, the recently released tax returns appear to undermine this argument as well.

Specifically, these returns demonstrate the former President Clinton made tens of millions of dollars on the speaking circuit and by helping to broker business deals or make introductions around the world. This is his prerogative as a private citizen. What the returns do not tell us, however, is who paid for these speeches; who his clients were/are; whether he can unwind his business relationships (he is being sued by one of his clients for fraud in state court in California); what conflicts of interest or appearances of conflict reside in his seven-year, private-sector career. (Remember the difficulty Geraldine Ferraro's husband created for her candidacy?). A lot more openness and transparency will be required by Bill Clinton before it is known just how vulnerable Hillary Clinton is as a general election candidate.

Still, the Clinton Library has yet to provide the list of its largest donors, or explain how their donations were solicited; as well it is not yet known whether Hillary Clinton played a role in President Clinton's pardon decisions including the 11th-hour pardon of Marc Rich. The Republican National Committee and related advocacy groups will surely allege a coverup if all this is not disclosed before the general election.

Unless all this material is released and vetted fully before the primaries come to an end, Mrs. Clinton is asking Democrats to make a leap of faith that nothing will be revealed in the general election campaign that could prove fatal. From what is available presently, Mrs. Clinton may prove to be the most vulnerable Democratic candidate in the last three election cycles.

It has been said that those who do not learn from history are doomed to repeat it. There are warning signs that Democrats may be walking down that same path with Hillary Clinton.