There was a study done years and years ago that calculated an average car (which at that time meant 30 mpg burning petrol and lasting 100,000 miles or 10 years), would take 3 times more energy to manufacture than that vehicle would have burnt.
So if we are truly interested in reducing greenhouse gases the immediate short time answer is to make the vehicles last longer.
And they have, there are 10 year old cars in the scrap yard now that I would have given my left arm for 30 years ago, nothing really wrong with them other than "we the consumer" want new and better and to hell with the environment or worse still, we think we are doing the right thing by replacing "old" cars and going for first diesels to increase the mpg and then silly hybrids because diesels kill everything, and now electrics.
The only sensible place that I can see for an EV is in the town/city because of the no point of use pollution, but will that really make any difference when the biggest polluters of all in cities are, building heating, buses, diesel trains, delivery vans and taxis, I doubt it...