In the early 1900s, as war moved into the sky from its traditional venues of land and sea, Glenn L. Martin founded an airplane manufacturer to launch defense contracting in the same direction.

The company set up in Maryland, near its moneybags federal customer, the U.S. Army Air Corps, and made millions designing and assembling bombers and flying boats in World War II. Its descendant is an important piece of today's Lockheed Martin Corp., based in Bethesda.

Now that warfare is entering yet another dimension, Harford County-based SafeNet wants to be the Glenn L. Martin Co. of the Internet and sell the cyberspace version of the B-26 Marauder.

SafeNet's public stock offering, announced last week, says much about the growing recognition that the more reliant we become on computer networks, the more vulnerable we are to electronic attacks.

Both Democratic Gov. Martin O'Malley and Republican challenger Robert L. Ehrlich Jr. boast about Maryland's strengths in cybersecurity. O'Malley wants the state to be "the nation's epicenter" for cyberdefense.

A bipartisan bill in Congress would put a cyberdefense center in the Department of Homeland Security and a permanent cybersecurity coordinator in the White House. The Commerce Department is pushing "cybersecurity education." The U.S. Naval Academy in Annapolis wants to construct a building for its new Center for Cyber Security Studies.

"After land, sea, air and space, warfare has entered the fifth domain: cyberspace," The Economist magazine wrote two weeks ago.

The Russians and the Chinese are probably working on "logic bombs" and other "virtual explosives" that could be launched with the efficiency and speed of a junk e-mail attack, only with much worse consequences, former White House counterterrorism adviser Richard A. Clarke writes in a new book, "Cyber War."

Power grids could be knocked out, he writes. So could oil pipelines, Wall Street, air-traffic control, and phone and television networks.

"A sophisticated cyberwar attack by one of several nation-states could do that today, in 15 minutes, without a single terrorist or soldier ever appearing in this country," Clarke writes.

Many have criticized Clarke of exaggeration and scaremongering. But still, what a setup for SafeNet's return to the public markets.

"Several key trends are driving the need for our high-end data protection solutions," the company says dryly in the prospectus for what looks like one of Maryland's biggest public stock offerings in years.

SafeNet has been around since the 1980s and became notorious a few years ago for a stock-options "backdating" scandal in which its former chief financial officer went to prison and its former chief executive paid a penalty to settle civil charges from the Securities and Exchange Commission.

Vector Capital, a private-equity outfit based in California, took SafeNet private three years ago. SafeNet's management and its entire board have changed since then.

Of course the odds are against the company's becoming the Lockheed Martin of cyberdefense, the cybersecurity boom notwithstanding.

Mark A. Floyd, the chief executive who joined SafeNet a year ago, may be likely to sell the company at some point. In two previous CEO posts, he sold information-technology concerns to Ericsson and Siemens.

In any event, cybersecurity is hugely competitive. RSA, Symantec and McAfee compete for SafeNet's customers. Protecting electronic information isn't as capital-intensive as, say, building an F-35 fighter. So barriers to entry for rivals are low, and customers may be more likely to do the work in-house.

SafeNet has become less reliant on the Pentagon as a customer, but 43 percent of its 2009 revenue of $400 million still came from the U.S. government, mainly the Department of Defense, the prospectus shows. SafeNet's losses over the past five years have shrunk, but they are still losses. The company may use some of the $300 million in proceeds from the stock offering for acquisitions, a possibility that should give potential shareholders pause.

SafeNet's previous management bought MediaSentry, a company hired by Hollywood to bust college kids downloading pirated movies and music. In the wake of terrible publicity, the Recording Industry Association of America dumped MediaSentry. SafeNet sold it at a big loss last year.

But even if SafeNet doesn't prosper from the cyber-defense boom, Maryland will. This state profits every time war marches into a new realm, as shown by the Naval Academy, the ordnance testing center at Aberdeen Proving Ground, NASA's Goddard Space Flight Center in Greenbelt, Fort Detrick's biological warfare expertise and the old Glenn L. Martin site in Middle River, which these days makes electronics to launch missiles.

And the business of defense contracting in the fifth domain looks here to stay.

Jay.hancock@baltsun.com