Toyota just launched its most miniscule production vehicle yet, the iQ. The tiny 55-miles-per-gallon four-seater will make its debut in Japan before the end of this year, and begin European sales in early 2009. Now that it’s headed to roadways in Japan and Europe, the question is whether or not the iQ will make it across the Pacific. And more importantly, are Americans ready for a call this small?

The Toyota iQ would comfortably slot in below the subcompact Yaris. But if the iQ does head to the US, specific modifications with respect to safety and structure would have to be made. The most significant changes would have to do with rear passenger protection. Even though the iQ is the world’s first vehicle to feature a rear window airbag, there is still a strong concern for passenger safety in a collision from behind. One proposal is to convert the iQ into a two-seater, eliminating the risk for back seat occupants.

As Toyota, Volkswagen, and other foreign car companies move in the direction of smaller, more efficient cars, it is important to note that American-based manufacturers like GM are showing little interest in pursuing the global microcar segment. In an interview with Automotive News, GM Europe President Carl-Peter Forster said, “These specialized urban vehicles have a limited market. I think the sweet spot is where we are with the Chevrolet Matiz.” The Matiz is a four-door subcompact—approximately the size of a Chevrolet Aveo—that has been criticized for its underwhelming styling. Some are surprised at GM’s unwillingness to go smaller in order to offset the fuel economy of its larger trucks and SUVs.

Toyota promotional video for iQ concept car.