H.G. Wells published “War of the Worlds” in 1898, yet 107 years later, this science-fiction classic remains relevant both politically and as an emotionally powerful evocation of our worst fears.

Director Steven Spielberg’s film adaptation, in theaters today, is the latest incarnation of Wells’ story of an alien invasion.

The idea of something terrible and unknown coming into a world we take for granted is “a story that taps into a deep level of fear,” said University of South Carolina English Department chairman Steve Lynn, who teaches science fiction classes.

Wells also provides a satisfying catharsis for the tension and the sense of impending doom he created when a virus halts and then destroys the invaders in “War of the Worlds.”

“We end up surviving through some kind of chance. Bacteria saves us,” Lynn said. “The message it sends is, we are not as powerful as we thought. We are extremely vulnerable and easy targets.”

How Spielberg’s movie portrays this fear and the subsequent catharsis remains to be seen, but previous adaptations provide some clues.

Well’s invasion theme proved relevant several times in our history. Historian and science-fiction enthusiast Terry Lipscomb said Wells, a staunch socialist, took great delight in having Martians lay waste to what the author saw as inhumane industrialized capitalism on the rise in the late 19th century.

Lipscomb added that when producer George Pal crafted his well-made version of “War of the Worlds” in 1953, the Cold War and related fear of nuclear annihilation were reflected in his film.

Previously, “War of the Worlds” acquired great notoriety in 1938 with Nazi Germany on the rise in Europe. The story was adapted then by Orson Welles as a radio play, and thousands of listeners – believing it was a true news report- fled into the streets, out of towns and even to local police stations pleading for protection. Welles, a well-known theatrical actor and director, subsequently apologized on the air and in the newspapers for setting off such widespread panic.

“War of the Worlds” also provided the underlying structure of two entertaining 1996 films, the gung-ho “Independence Day” and the comical take-off on 1950s sci-fi cinema, “Mars Attacks.” A computer virus saves mankind in the former film, while country singer Slim Whitman’s yodeling proves amazingly lethal to invaders in the latter.

Five years after the release of these films, the World Trade Center was attacked and destroyed by terrorists. In a post-9-11 world with an ongoing war in Iraq, terrorists have been the contemporary embodiment of Wells’ alien invaders.

When Spielberg said his “War of the Worlds” invaders would not be Martians, it didn’t surprise USC film professor Ina Hark, who teaches science-fiction film courses. The once-mysterious planet does not hold so many secrets anymore.

“We’ve seen Mars. It looks like the Mojave Desert,” Hark said.

Cyber worlds and microtechnology, not outer space, are what now capture the popular imagination, said South Carolina librarian and sci-fi fan Darion McLeod.

“The pop culture is apathetic about space exploration now,” McLeod lamented.

This shift also is reflected in other Spielberg movies. His 1977 “Close Encounters of the Third Kind” and 1982’s “ET: The Extra-terrestrial” were fueled by the desire to make contact beyond Earth. Spielberg’s aliens in both films were gentle, beneficent creatures, while human scientists and bureaucrats were the villains.

Spielberg’s 2001 film, “AI: Artificial Intelligence,” portrayed Stanley Kubrick’s darker view of the future through Spielberg’s typically more optimistic sensibilities. Kubrick had commissioned the script and originally planned to direct.

In 2002, Spielberg showed his own darker vision of science fiction with “Minority Report.” But again, aliens were not the enemy in this futuristic world.

Whatever form the alien invasion takes, Hark suggested the origin of our fear is “probably an instinctual nightmare – to go from prey to predator but always worrying about being prey again.”