To all public officials: Put down your BlackBerry and step slowly away from the weapon. By now you should know that the convenience of e-mail masks many dangers. After all, senior White House officials and their aides have had access to electronic messaging for four administrations — going back to an early e-mail system IBM installed for Ronald Reagan’s national security staff 25 years ago.

The risks for public officials are only growing with the latest generation of high-tech office systems. The software and telecom companies that offer these systems promise “integrated” or “unified” communications solutions — with e-mail, telephone calls, voice mail, online meetings and even video messages all flowing through one electronic in box. Messages in whatever form are accessible from a BlackBerry or some similar pocket-sized device. And they can easily be shared. Or leaked. Or subpoenaed.

In other words, get ready for the multimedia document dump.

This vision, both seamless and permeable, should terrify any elected or appointed officials who have been reading about the e-mails sent by some of their garrulous colleagues at the Justice Department and the White House. The controversy over the eight ousted U.S. attorneys largely boils down to who e-mailed what and when did they e-mail it.

Those officials clearly forgot or disregarded one of the most reliable political rules of this computerized age: Never put anything in an e-mail message that you wouldn’t want to read on the front page of The Washington Post. So here we are again, watching ravenous reporters feast on newly released internal communications, this time from an administration struggling to square its initial explanations with all of that e-mail before more senior officials are devoured.

Remarkably, much of the e-mail appears to have been sent just as the Justice Department was prosecuting a slew of other public officials with ties to lobbyist Jack Abramoff — including White House procurement official David H. Safavian, who was convicted in large part because of his own e-mail messages.

Many in public life still allow the casual efficiency of electronic correspondence to distract them from what they’re doing: creating a public record. And more and more of what they do is essentially becoming public, as the new generation of office systems make recording teleconferences and the associated presentations (slides, spreadsheets, documents) as easy as clicking on a button. These systems make archiving and record management easier, too, which increases both efficiency and danger in parallel. Laws and regulations protect some of this communication, but those rules change almost as fast as the technology does. And leaks are rule-proof.

We’ve already seen long-distance videoconferences — including the pre-Katrina recording of President Bush getting briefed on the possibility of massive hurricane damage in New Orleans and on the Gulf Coast — resurface to cause political embarrassment. Public officials now need to be prepared to relive that time they left a screed in an underling’s voice mailbox when it’s played by NPR or CNN.

Online communication tools revealed their dangers to those in government almost as soon as they were installed. Many details of the Reagan administration’s plans to trade weapons with Iran for help releasing U.S. hostages in Lebanon, and to use the profits from those deals to fund anti-communist fighters in Nicaragua, emerged from electronic messages exchanged by National Security Council officials. National security adviser John Poindexter and aide Oliver North deleted thousands of those messages in November 1986, just as the story of those transactions began to leak, but investigators recovered most of them from backup tapes.

Most organizations, public and private, have policies that detail what employees may and may not do online. The chief information officer for the Commerce Department has a broad “Internet Use Policy,” for instance, that specifically prohibits employees from “engagement in any activity that would bring discredit on the Department.” But such rules rarely provide advance immunization against electronic embarrassment. Instead they are most useful after the “discredit” has been done, when the time comes for someone to pursue new opportunities in the private sector.

Advising those who have not learned from the mistakes of Poindexter, North and all of the other errant e-mailers since is not in my journalistic interest. Instead, I can only pass along President Bill Clinton’s April 2000 advice for all 21st century public servants. After Clinton spoke about the marvels of the digital age at an event in East Palo Alto, Calif., a nine-year-old asked the president how he used the Internet. Clinton told the boy that he had gone online to order Christmas presents but confessed that he was reluctant to send messages electronically.

“If you work for the government,” Clinton said, “you don’t use e-mail very much unless you want it all in the newspaper.”

That’s a message worth remembering the next time anyone in public life gets ready to click on the “send” button.

Mark Stencel is deputy publisher and a technology columnist for Governing magazine, published by Congressional Quarterly Inc.