In 2000, President Bill Clinton took a pot shot at the Republican presidential candidate George W. Bush saying, "The message of the Bush campaign is just that, 'How bad could I be? I've been governor of Texas. My daddy was president.'"

cheneyThat got George H.W. Bush's blood boiling.

"I'm tempted to come off the reservation," said Poppy at the time. "And if he continues that, I'm going to tell the nation what I think about him as a human being and a person."

The "reservation" Bush Senior was talking about is the one former presidents and vice presidents retire to after their terms are over. On it, no ill is spoken of the current administration.

It's an unwritten rule but an important one. Former presidents and vice presidents know they are no longer privy to the insights and intelligence the president and his administration receive so second guessing the country's leadership could make them look bitter, ill-informed and undignified.

In Clinton's case, he was merely campaigning for his man Al Gore, although I agree with Poppy that 42's characterization of Bush Junior was unpresidential.

That's why I wish Dubya or his dad would speak up now and tell former Vice President Dick Cheney to shut up.

When he served as Secretary of Defense in the first Bush administration, I had a lot of respect for Cheney. He oversaw the masterful Desert Storm operation that kicked Saddam Hussein out of Kuwait and sagely advised President Bush not to chase the tyrant back to Baghdad.

In a 1994 interview, which is available at YouTube, Cheney said America would have found itself in a "quagmire" had we invaded Iraq, rhetorically asking how many U.S. lives were worth spending to take down Saddam. "Not many," he said then.

Seven years later, post 9-11, Cheney inexplicably changed his tune. Suddenly, invading Iraq was the thing to do even though Saddam had no hand in the worst terrorist attack in American history, which happened on the Bush-Cheney watch.

In the run-up to the invasion, when the Bush administration officials were exploiting public fears of terrorism by invoking terrorist mushroom clouds, no doubt Cheney believed the attack on Saddam would go like Desert Storm, quick and almost bloodless, even though it was he who predicted chaos if Iraq's government was toppled.

No WMD, no problem as long as it went down before anyone noticed.

We now know the 1994 Cheney was spot on and the 2002 Cheney was dead wrong. Ten years, 4,487 American dead, and at least $1 trillion in borrowed money got us nothing but quagmires and chaos.

If Cheney had gone quietly to that reservation, humbled at being so completely wrong about so much, he'd be fading from America's collective memory by now.

Instead Cheney has become a regular and unhinged critic of President Obama, violating presidential decorum and revealing himself to be, yes, bitter, ill-informed and undignified.

After multiple heart surgeries, the 73-year-old Cheney is likely on the last of his nine lives so he appears desperate to rehabilitate his own shattered legacy by savaging Obama's.

His June 18 Wall Street Journal op-ed, co-written with his screechy offspring Liz, is a great example, casting the president as a feckless dilettante more intent on his golf handicap than stopping terrorism, which of course is nonsense.

It was Obama who took down Osama bin Laden, whom the Bush administration couldn't catch for seven years. It was Obama who killed or captured dozens of terrorist leaders, most recently the Libyan who allegedly led the attack on the U.S. diplomatic outpost in Benghazi.

Does anybody other than cranky old men watching Fox News really care what Dick Cheney thinks anymore? His former boss, George Bush sure doesn't.

By the end of their second terms, according to the film "The World According to Dick Cheney," Bush was barely speaking to his vice president.

I'm beginning to understand why.