Robert Soloway – aka “the king of spam” – deserves a reserved seat deep in Dante’s Inferno. But four years in a federal prison will do for now.

Actually, it’s surprising and sweet that any spammer-royale has gotten caught, prosecuted and duly punished. They’re adept at working underground, and many of them operate from countries where dumping millions of unwanted commercial and fraudulent e-mails into people’s inboxes seems to be perfectly legal.

Soloway, however, was operating in Seattle. He was convicted of fraud and tax evasion there and sentenced Tuesday in U.S. District Court.

There are people out there who defend spam as another form of free speech. Sorry: apples and oranges.

Free speech is standing in a park haranguing passers-by. It is griping about the government without a goon squad knocking on your door in the middle of the night. It is heckling a candidate from a reasonable distance.

Free speech isn’t breaking into a stranger’s house and pestering him to buy illegal pharmaceuticals, hook up with a beautiful-but-bored neighbor or accept fortunes from fugitive African officials. The key element is invasion of the privacy of other people’s computers.

Spam isn’t a minor annoyance. It’s theft of time and money on a planetary scale. Billions of unsolicited e-mails jam the inboxes of humanity every day. Many people have to spend hours a week killing deceptive come-ons out of their systems.

Internet service providers – and, indirectly, their subscribers – waste untold millions handling the daily onslaught of spam. ISPs and their customers must buy software to filter it out, then buy new software when the likes of Soloway figure out ways to get around the old software.

Soloway was a particular sweetheart. He would refuse to take people off his mailing list when they requested it. Critics say he “mail-bombed” their computers. His victims were sometimes forced to flee their domains or spend thousands getting his messages to stop.

A nasty guy. But Soloway did possess one wonderfully redeeming quality: He was sloppy enough to get caught. Unfortunately, there are a lot more “kings of spam” out there. May his fate put the fear of God into them.