Peter Holley:

Electric vehicles no longer seem like a futuristic fever dream, but they remain a rarity on most American city streets, accounting for less than 1 percent of the nation’s auto sales, according to the automotive website Edmunds.com.
 
 Yet, when future auto historians look back, they may pinpoint 2017 as the year electric vehicles went from a promising progressive fad to an industry-wide inevitability.
 
 Related: [Death of gas and diesel begins as GM announces plans for ‘all-electric future’]
 
 The tipping point, experts say, follows three developments, each rippling outward with economic and cultural consequences.