400 or 1200 hours? That would depend entirely on how well he or she flies the airplane, his willingness to learn and adapt to different situations and most importantly attitude. I think that Josh, Boiler and Schone made excellent points regarding this.

As has been mentioned before, the Europeans have been putting extremely low time pilots in the right seat for years and the aircraft aren't falling out of the sky (and I'm referring to Western Europe, not Eastern Europe, Central Asia, North Africa etc. who face an entirely different set of challenges...).

It is true that the training and selection process is different in Europe. The process of selection is more rigorous and the training is often airline orientated from day one. That being said, the most significant difference is that more Captains accept their role as a mentor so that the FO may become a more skilled and well rounded airline pilot and future captain.

Since lower time pilots are once again a reality here in the US, would it not make more sense for those in the left seat to adopt a more pragmatic attitude regardless of their personal feelings? If the person in the right seat is proficient, knowledgeable and willing to learn, why not help him become the more experienced well rounded pilot you would like sitting beside you?

As others have mentioned, times have changed and you can not really blame a pilot for taking an opportunity that was not available to those who came before him. To those who are so adamantly against the lower time pilots, can you honestly say that you would have turned down a job had it been offered to you when you were low time? That being said, I think the selection criteria should be stricter for lower time pilots. The candidate must have a certain level of maturity and life experience.