As of May 19, 2009, Nevada amended its state transportation laws to explicitly permit electric bicycles to use any "trail or pedestrian walkway" intended for use with bicycles and constructed with federal funding, and otherwise generally permits electric bicycles to be operated in cases where a regular bicycle could be. An electric bicycle is defined as a two- or three-wheeled vehicle with fully operable pedals with an electric motor producing up to 1 gross brake horsepower and up to 750 watts final output, and with a maximum speed of up to 20 miles per hour on flat ground with a 170-pound rider when powered only by that engine.[106]
Electric powered bicycles slower than 20 km/h without pedaling are legally recognized as a non-mechanically operated vehicle in China.[32] According to "TECHNOLOGY WATCH", this should help promote its widespread use.[33] Electric bicycles were banned in some areas of Beijing from August 2002 to January 2006 due to concerns over environmental, safety and city image issues. Beijing has re-allowed use of approved electric bicycles as of January 4, 2006.[34] Some cities in China still ban electric bikes.

(15.5) "Electric assisted bicycle" means a device with two or three wheels which has a saddle and fully operative pedals for human propulsion and also has an electric motor. For such a device to be considered an electric assisted bicycle, it shall meet the requirements of the Federal Motor Vehicle Safety Standards, as set forth in 49 C.F.R. Section 571, et seq., and shall operate in such a manner that the electric motor disengages or ceases to function when the brakes are applied. The electric motor in an electric assisted bicycle shall:

Electric bikes (also known as e bikes) are perfect for long-distance riding, or when you just don’t feel like giving your full effort. What differentiates them from electric motorcycles is the ability for the rider to pedal the bike at any time, so if you’re riding along and your battery dies, you’re not going to stranded. These are often very valuable bikes, but some models can be more affordable than you might expect, especially when you treat them as a form of transportation as opposed to thinking of the price in terms of regular bicycles.
Built around a heavy-duty alloy frame, the GSD eschews many of the traits of other cargo bikes: long wheelbases, bigger wheels, and especially, an unwieldy ride. Yet it boasts an extensive capacity, nimble handling—even fully loaded, thanks to a short wheelbase and 20-inch wheels—and enduring range in a package not much bigger than most non-cargo e-bikes. The stout frame holds a 250-watt Bosch motor that gives up to 275 percent of your power back to the pedals and reaches 20 mph. The GSD has room for two battery packs, extending the batteries’ combined range to a claimed 150 miles and making the Tern one of the longest-lasting e-bikes on the market. A laundry list of accessories and a (claimed) 396-pound carrying capacity round out the GSD’s status as an epic day-tripper.
The pedals on a motorised bicycle must be the primary source of power for the vehicle. If the motor is the primary source of power then the device cannot be classed as a motorised bicycle. For example, a device where the rider can twist a throttle and complete a journey using motor power only without using the pedals, would not be classed as a motorised bicycle.
I would add that the point of the article seems to encourage ebikers to “know the state laws” and be confident within those boundaries. To D McCarthy’s question, if your state has a definition for ebikes and classifies them as bicycles and affords access as bicycles, AND, your particular ebike is built within those specifications, then you should be able to ride that section of road with confidence. Just my 2C.
Perhaps the cleverest thing of all about the Electric Brompton is that despite all the extra stuff, it folds up exactly the same as the non-powered variety. It's so simple, and unlike certain folding bikes we could mention, what you're left with is a genuinely small thing, rather than something that's about the size of a bike with the front wheel taken off.