Happily, this co-operation across borders is breeding success. The new Ford looks, inside and out, more like a premium car than ever, and an ideal replacement for the current Mondeo that continues ton earn plaudits. The Dodge, despite a hint of the jelly-mould about its flanks, has enough about it to please the traditionalists. Add to this GM's impressively taut and compact new Cadillac ATS (in size, if not spirit, successor to the unlamented BLS) and you have three credible, desirable saloons. One demerit for the Cadillac; once again GM talking about going European without waiting for a diesel to come on stream. Note from your man on the doorstep: it can't work.
Bentley don't have diesels yet, either, but they constructively showed their new 4.0 litre turbo V8 engine, plus some two-door Continental models subtly redecorated to take it. Without quite promising it, they made it clear that the new car will go close to halving the the 6.0 litre W12's fuel consumption, while still delivering huge performance. Mercedes were also talking high performance efficiency: their new aluminium-magnesium SL takes the long-lived two-seater model back to the realms of genuine sports cars from which it departed a couple of decades ago.
BMW showed the new 3-series, no longer news in Europe but certain to be successful in the US as it is wherever rational motorists can be found. Hyundai re-nosed the Genesis coupe and showed a turbo version of their oddball Veloster, a move that happily helps demonstrate that performance isn't something they'll shy away from forever.
King of the concepts? For me, Honda hit the high spot with its long-awaited NSX hybrid "two electric" supercar concept, which shows (as if we didn't know) that it has always needed a super-efficient performance flagship. Making it in the US makes sense if it to find the buyers the old model lacked, but we are disappointed to learn the car is still nearly three years away. Will it ever be closer? Lexus also excelled via the beautiful LF-LC hybrid coupe, which the company says carries the design cues ofva string of new production models. Bring 'em on!
Also impressive was the Smart For-us concept, ostensibly a neat-looking plug-in pick-up for carrying electric bikes, but considerably more important than that. Its wheelbase had been extended by 40cm, which showed that the four-seater version hinted at under a forthcoming Daimler - Renault cooperation could indeed be built using the existing rear-engined mechanical layout.
Opinions varied about GM's oddly-named Californian concepts (Code 130R rear drive, four-seat coupe and Tru 140S front drive coupe) but to me they looked rushed and didn't match the Honda-Lexus-Smart standard or significance. One hopeful official referred to the 140S to a GM equivalent of the Peugeot RCZ - which only goes to prove that in 2012 Detroit, optimism remains alive and well.