The trickle of European and Japanese small cars into the U.S. is slow but steady.

We've got the MINI, we have the Fiat 500, and Ford and Mazda have graced us with the Fiesta and Mazda2. Compared to overseas markets though, there's still a lot of small metal that we're missing out on.

So where are they, and how long do we have to wait? Below are the main protagonists...

Ford Ka

Our first forbidden fruit is already Federalized. "How?", we hear you ask. "Because it's a Fiat 500", we say--that's right, underneath the mini-Fiesta body is the inner-workings of a Fiat 500.

The interesting aspect to this one--and one that would probably cause a rip in the space-time continuum--is that thanks to the Fiat ties, the Ka is actually a Ford-Chrysler. Or a Chrysler-Ford. Either way, it ain't gonna happen.

Volkswagen up!

We drove the up! a month or two back in the U.K, and it's one of the best small cars we've ever had the pleasure to drive. It manages the trick of feeling like a larger car than it is--not just in terms of interior space, but also in refinement, interior quality, and ride quality too.

With VW reluctant to sell even the Polo over here though, the up! is extremely unlikely to arrive in the U.S. any time soon. That's a pity, as with a slightly more potent engine--up!s come with either 59 or 74-horsepower 1.0-liter units--it would have a real chance against cars like the Fiat 500.

Nissan Micra

The Micra is accompanied by a curious rumor. The car is already Federalized, for Penske--as it was intended to become a four-door, four-seat subcompact to be sold under the Smart brand.

That idea seems to have disappeared into the ether, but technically it means Nissan wouldn't have to do much work to launch its Fiesta rival into the U.S. Apart from spruce up its image, since the odd styling wouldn't win many fans...

Mercedes-Benz A Class

This one could well be coming to the U.S. Mercedes has made significant changes to its A Class model, morphing it from a tall, practical vehicle into something with a lot more style. It's now a true competitor for cars like the Audi A3, and in the U.S. it will be sold with a range of efficient yet potent turbocharged gasoline engines.

Volkswagen Polo

Volkswagen has been teasing us with the Fiesta-sized Polo for years. Slotting between the Golf and the up! in VW's lineup, the Polo is offered in Europe with a huge range of engines, from naturally-aspirated 1.2-liter gasoline units, through twincharged 1.4s, to turbodiesels.

It wins wide praise too for its clean styling and solid build, even if it's less exciting than the Fiesta. But VW doesn't seem keen to sell anything smaller than the Golf on U.S. shores, which is a pity.

Alfa Romeo Mito

Alfa Romeo Mito

Alfa Romeo MiTo

Dodge has been at pains to remind us of the link between the 2013 Dodge Dart and the Alfa Romeo Giulietta, a compact car sold in Europe. The MiTo is the Giulietta's smaller brother, based on the Fiat Punto platform, which also underpins the U.S.-focused Fiat 500L.

Potentially Chrysler could sell the Mito as a rival to cars like the MINI, and it's certainly more spacious than the Fiat 500. But unfortunately, this one is unlikely to come to the U.S, either as an Alfa or a Dodge.

Chrysler Ypsilon

Here's an even more confusing one. The Chrysler Ypsilon is only sold as a Chrysler in the U.K, where Chrysler have had small sales successes over the years with cars like the PT Cruiser.

Except the Ypsilon is really a Lancia, a brand sold in Europe, but not in the U.K, where the Italian marque gained a poor reputation for rust. But really the Ypsilon is based on the Fiat 500 platform (formerly the Fiat Panda platform, and the aforementioned Ford Ka...), a car that is sold in the U.S... by Chrysler. So really, the U.S. already gets the Chrysler Ypsilon, even though it doesn't.

Told you it was confusing...

That's quite a list of forbidden fruits then, and only a few will ever make their way onto U.S. soil. That's a pity, because all are talented vehicles--but it may still take a few years for U.S. buyers to be truly comfortable sharing the roads with huge SUVs in their tiny European cars...

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