Let's try to be clear about terms. If it runs entirely in an exclusive right-of-way, it's light rail, not a streetcar.I agree with Tcmetro and Tmart that we need a proper streetcar, one that is protected from cars.Most other US streetcars suck because they implement little or no priority measures, operate in cities that have weak transit systems, and circulate low-population downtown areas. The Nicollet-Central streetcar as currently envisionsed is too short to be successful, but a longer one would take the bulk of current bus rides.
Arterial BRT is nice, but it's not revolutionary. It adds fancy bus stops and prepayment and a simpler service pattern.
If we go with streetcar, it should be a proper one. The true analysis should be between a proper streetcar and a real BRT. These would be much more transformative than either arterial BRT or a mixed-traffic streetcar.
Nobody has given up on rail. But that's not the same as pushing for rail when it doesn't make sense to do so. In an ideal world, the Nicollet-Central corridor would be served by subway. But nobody is pushing for this, because it is obvious that the monetary and political costs are prohibitive.Why have we given up so easily on rail? We need to push harder, not kowtow (or worse, actually believe) the whims of people in the pocket of big oil who are trying to destroy transit.
Does it then follow that a streetcar is the best option? Not necessarily. Because again, we need to talk about costs and benefits. What are the benefits to a streetcar and how do they compare to the benefits of aBRT? What are the costs of a streetcar and how do they compare to aBRT?
I've ridden streetcars in six US cities. I'd rank the experience as basically identical to the A or the C Lines. But if for some reason, you really enjoy a streetcar, what kind of premium would you put on the experience? Is it twice as nice as aBRT? Is it three times as nice? Because even if you come to that conclusion, you need to reconcile it with the fact that aBRT's costs are, (just taking a quick look at figures from Google) about ten to twenty times lower per route mile than a streetcar.
Streetcars are bad not because they are awful products on their own, they are bad because the are terrible value. You could build ten to twenty times as much high frequency transit (with the added bonus of being more resilient to changes like road closures, accidents and blockages), if you spent your money on aBRT.