One June 17, 40 years ago, five men broke into Democratic offices at the Watergate hotel and office building, and were caught - an event that would change both politics and journalism in the United States.

Bob Woodward and Carl Bernstein, the reporters who broke the story, still sound amazed.

"This story was like getting into a warm bath, and then it got hotter and hotter and hotter, so we were able to withstand the heat," Bernstein said, as the two were interviewed by CBS's Charlie Rose tonight at The Watergate complex in Washington, D.C., at an anniversary event hosted by The Washington Post, the newspaper for which Woodward and Bernstein broke the scandal.

"The most remarkable thing was, early on, about eight weeks after the break-in, we found out that [then-Attorney General] John Mitchell … had controlled this secret fund," Bernstein said, recounting how both of them realized President Richard Nixon would be impeached for corruption.

"The stakes at that point became so obviously huge, at 28, 29 years old, every morning the leader of the free world is getting up and [criticizing] … our conduct specifically," Bernstein said.

What stands out for the two journalists, they say, is the brazen depravity with which Nixon and his operatives sought to undermine democracy and squash their political adversaries, assumed to be justified during the Vietnam war by national-security pretenses - not just pertaining to the Watergate break-in, but to systematic abuses. The "horrors" of the Nixon White House, they said, are astonishing when heard firsthand on the former president's Oval Office tape recordings.

"The most insidious one was Nixon and his people saying we're going to hire spies and saboteurs, and we're going to pick who Richard Nixon runs against, and if you look at the record, they helped derail [Democratic presidential-primary candidate] Sen. Muskie, and [eventual Democratic nominee] Sen. McGovern got the nomination," Woodward said.

"It's really an attack on the free electoral process to say … 'let me pick who I think will be the weakest candidate," Woodward said. "And the idea that somebody is going to do that who is president of the United States … is pretty horrifying."

For both, the meaning of Watergate first and foremost is a lesson about Nixon himself.

"This was about a president that used illegal, unconstitutional means as a basic matter of implementing policy, and that's what makes this unique in our history," Bernstein said.

"Richard Nixon did not understand what the presidency was, that there was this good will that flows to any president, and it is something that he could not use because he was driven by, 'Oh, so and so is an enemy, let's get the IRS on them. Oh, we don't like the Brookings Institution, let's break into the office there,'" Woodward said. "It is not only the illegality and the abuse of power; it's the smallness of Richard Nixon."

Preceding Woodward and Bernstein at the Post's event were other key players in the scandal, including Nixon's White House counsel John Dean.

"The coverup really starts within the moments of the White House learning about the fact that five men had been arrested here in this building wearing business suits and rubber gloves … and that they're from the reelection committee," Dean said. "They put out a press release which was completely bogus. … The die is cast that week."

Former Sen. Fred Thompson, who served as a counsel to the Senate Judiciary Committee during its investigation of the Watergate scandal before being elected to the upper chamber himself, said the scope of the scandal went beyond anything imagined at the time.

"I think most of us thought that, in the typical campaign fashion, there was some young, inexperienced overaggressive people who had done some things that were stupid," Thompson said. "That certainly never occurred to me that the president of the United States, for example, or his key people, would be involved in something so ridiculous both from a moral standpoint and from a practical standpoint … it was a totally botched job."

A minor theme recurred through the evening's discussion: Now that America is in wartime again, have attitudes changed sufficiently since Watergate that national security is no longer can be used as a moral excuse for abuses of power?

"Not enough's changed. I think we saw repetition of it in the Iran Contra [during the Reagan administration] … I think that was almost as dangerous to the system as Watergate was," said William Cohen, a Republican member of Congress during the Watergate investigation. "We have to constantly understand we're never going to reach a plateau of perfection."