Here's what we know that we can be absolutely certain about:
John Kerry, like Al Gore, served in Vietnam in some fashion. President Bush did not, having used his father's connections to get into the Texas ANG. Similarly, our current Vice President and Secretary of Defense applied for, and received, at least four draft deferments each.
Kerry got shot at, more than once. Bush did not, and neither did our VP and Secretary.
Kerry received several decorations, and was sent home after his third Purple Heart, received (like the previous two) for relatively minor wounds.
Subsequently, Kerrey strongly and publicly criticized the War, and testified to this before Congress.
Kerrey's job record includes some years as a prosecutor and lieutenant governor before he became a senator. Bush's record includes three failed oil businesses, several years as an administrator for the Texas Rangers baseball team, and one term as Governor.
When Kerrey remarried, he married an extremely wealthy woman with a ketchup fortune. Bush comes from an extremely-wealthy family of Texas oil tycoons.
Democrats such as Kerry, and Bob Kerrey, and Max Cleland, and some Republicans such as John McCain, have repeatedly had their patriotism and character attacked by Bush's campaigns, as well as by various extremely-right-wing Republican organizations.
One of the heads of, "Swift Boat..." has been following Kerrey around since 1971, financed by right-wing groups, and appears to have no other profession.
Hm.