Vice President Cheney mocked Vice President-elect Joe Biden's grasp of the Constitution, defended former Defense Secretary Donald Rumsfeld and said President Bush "doesn't have to check with anybody" before launching a nuclear attack.

In a blunt, unapologetic interview on "FOX News Sunday," Cheney fired back at Biden for declaring in October that "Vice President Cheney has been the most dangerous vice president we've had probably in American history."

"He also said that all the powers and responsibilities of the executive branch are laid out in Article I of the Constitution," Cheney said in a interview that was conducted on Friday. "Well, they're not. Article I of the Constitution is the one on the legislative branch."

"Joe's been chairman of the Judiciary Committee, a member of the Judiciary Committee in the Senate for 36 years, teaches constitutional law back in Delaware, and can't keep straight which article of the Constitution provides for the legislature and which provides for the executive. So I think I'd write that off as campaign rhetoric. I don't take it seriously."

Cheney, who is often called the most powerful vice president in history, also challenged Biden's claim that the Bush administration has amassed too much executive authority, a trend Biden reportedly plans to reverse.

"If he wants to diminish the office of the vice president, that's obviously his call," Cheney shrugged. "President-elect Obama will decide what he wants in a vice president and apparently, from the way they're talking about it, he does not expect him to have as consequential a role as I have had during my time."