TOKYO—You’d think that nowhere in the world would be more excited over Guillermo Del Toro’s hotly anticipated “Pacific Rim” than Japan, the breeding ground of the imminent blockbuster’s dual strands of cultural DNA: kaiju — mammoth monsters — and mecha — giant robots.

In 1954, a titan rose from the depths of the nation’s collective unconscious: A mutated reptile with atomic breath and a yen for destruction named Gojira. According to its creators, the name was a portmanteau of the words for “gorilla” and “whale,” referencing the giant lizard’s power, strength and aquatic origins — but it was the English transliteration of his name that most effectively summed up his influence on the pop culture universe: Godzilla, the primordial kaiju, god of beasts, King of the Monsters. Even today, Godzilla remains one of the most globally recognizable fictional creatures in existence — a testimony to his continued relevance as the ultimate avatar of nuclear anxiety.

Two years later, Japan was also where manga artist Mitsuteru Yokoyama conceived the notion of a giant humanoid robot war machine, remotely controlled by the 10-year-old son of its late inventor. The robot, Tetsujin (“Iron Man”) 28, captivated fans throughout its home country and abroad, where it was better known by its translated title “Gigantor.” Over the next half-century, the mighty three-story-tall steel behemoth — and Yokoyama’s equally influential followup “Giant Robo,” whose live-action adaptation was distributed globally as “Johnny Sokko and His Flying Robot” — would launch a legion of imitations and innovations.

Del Toro has frequently cited these seminal Japanese pop culture genres as key influences on his aesthetic and narrative sensibilities. “I grew up on a steady diet of Japanese horror and science fiction,” he told Comic Book Resources. “We used to get a lot of Japanese TV — ‘Ultraman,’ ‘Space Giant’ — Mexico, for whatever reason, unexplainable to me, had a huge market for Japanese fiction.” Sharing his love of kaiju and mecha with a “new generation of children” was Del Toro’s primary motivation for developing "Pacific Rim," and having seen the film in all of its gear-grinding, beast-busting, city-smashing glory, I’m confident he’s accomplished his objective…at least where Western kids are concerned. As Del Toro has asserted, it’s not like anything they’ll ever have seen before: The massive, malevolent kaiju are implacably alien and monstrous; the equally immense Jaeger forces, each colossus piloted by a pair of harmonized human pilots, inspire involuntary cheers when they thunder ponderously into position to clash with the creatures, fist and cannon to claw and tentacle. The dialogue may be overwrought, the acting two-dimensional and the plot full of holes the size of the gargantuan combatants themselves, but as anyone who’s ever seen, say, “Godzilla vs. Megalon” would know, that’s pretty much par for the kaiju course: The film’s weaknesses end up being almost atmospheric.