Now that the 2015 model year is fully upon us, the decade is half-over.

And those kinds of milestones always lead writers to look back and assess how far we've come.

In the case of automobiles, we see three different vehicles launched over the last five model years that have radically changed the landscape.

READ: How Audi, BMW & Mercedes Plan To Compete With Tesla--And Why

Two are new models, one is a radically re-engineered continuation of tradition.

Each has its own pros and cons, so we're going to list them alphabetically.

2011 Chevrolet Volt

2011 Chevrolet Volt


The first high-volume electric car ever sold by GM--which less than a decade earlier had notoriously crushed its EV1s--the Chevy Volt was a surprisingly good car that made converts out of pretty much everyone who drove one.

The four-seat, five-door hatchback also launched a new powertrain concept that Chevrolet struggled unsuccessfully to explain.

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Its range-extended electric powertrain ran entirely on battery power for the first 35 miles or so (unlike plug-in hybrids that switched on their gasoline engines under full acceleration).

After the Volt's battery was depleted, then (and only then) would the engine switch to run a generator that produced more electric power.

But lower-than-projected sales, residual anti-GM hatred from its 2009 bankruptcy and taxpayer-funded bailout, and the confusion over a "35-mile electric car" meant that the Volt to this day is misunderstood by vast numbers of potential customers.

Still, anyone who drives a Volt comes away impressed--and the redesigned 2016 Chevrolet Volt promises to be an even better version with more range, more refinement, and (we hope) a lower price.

2015 Ford F-150

2015 Ford F-150

2015 FORD F-150

It's a fact that green-car advocates like to ignore: The best-selling vehicle in the U.S. has been the Ford F-150 full-size pickup truck. For three decades.

But the 2015 model is more than just all-new; it has a cab and pickup bed made entirely of aluminum, cutting 500 or more pounds out of the big truck to lower weight and help it meet steadily toughening Federal fuel-economy rules.

MUST READ: 2016 Chevy Volt: Bigger Battery, More Motor Power, New Range Extender Engine Details: EXPANDED

Ford's now-retired CEO Alan Mulally came from Boeing, and he gambled on taking aluminum out of its luxury-car niche (think Audi A8, Jaguar XJ, Tesla Model S) into half a million tough work trucks a year.

It's a revolutionary bet that big trucks can remain big, and continue to provide all the cargo space, towing capacity, and brute power owners have come to rely on.

How that bet will work out in practice has yet to be determined. But the aluminum F-150 is a big, bold, brash use of new technology in one of the most conservative segments of the market.

2012 Tesla Model S Signature

2012 Tesla Model S Signature


Finally, there's the beautiful, fast, unlikely Tesla Model S--still the world's longest-range, fastest, and perhaps best-looking electric car.

If the Tesla Roadster was the car that took electric cars out of the "golf cart" category, the Model S catapulted them into competition with the most prestigious brands in the business.

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Allied with a rapidly-spreading network of DC fast-charging "Superchargers" that give a Model S 200 more miles of range in under 20 minutes, the Model S has become all the things electric cars were never envisioned to be: high-performance, good-looking, comfortable, practical, long-distance, and just plain cool.

And that's not even mentioning the recent "D" all-wheel-drive option just launched last month, which makes the Tesla Model S the fastest production sedan in the world, with acceleration from 0 to 60 mph in just 3.2 seconds.

If Tesla survives, it'll be the first U.S. car company founded by entrepreneurs from the ground up in 80 years to make it.

But even if Tesla vanished tomorrow, we suspect the Model S will be viewed as a stunning landmark in the evolution of the automobile.

Meanwhile, here's the question we're turning over in our heads: If we had to pick just one of these three as the most important vehicle of the 2010s thus far, which would it be?


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