2.0 twin turbo, twin intercooled diesel. How hot is it now?

Up to 48 mpg. 140 mph top speed. 295 ft/lbs torque from a 2.0L diesel engine. In a Buick Verano, Regal, Encore and LaCrosse, this would blow eek-Assist into the WEEDS. No contest!

Something like this makes the future seem not so dark and dead. Why is GM not selling this engine in the USA?

That Cruze diesel had better be bulletproof, efficient, lively and affordable... because it could be the gateway to an electric-free CAFE compliant future.

Why is GM not selling this engine in the USA?

I would assume it's the same reasons as usual:

a) The US regulates emissions very differently from Europe, so it's likely to not pass as-is

b) The US changes diesel regulations way too frequently, so spending money getting something to pass is often not worth it, as the regulations end up changing almost immediately after the product is ready for market, so there's no time to recover costs and make a reasonable profit.

In other words, it's a political thing. Somebody wants the US to electrify its automotive fleet, and apparently it matters not whether the public at large wants it or not.