Martin did not fail in the US. He went there to talk not to broker deals. A relationship must come first before any understanding (or even wanting some understanding) can take place. My hat is off to Martin who straddles a sharp fence. If he doesn't build good will with the US he will have failed; if he builds too good of relationship with the US he will fail because we will boot him next election.
That's where Harper is in danger, IMO. Harper wants to emulate the US in too many ways. He has made and will continue to make the new CPC party into what comes down to the Republican Party of Canada. He doesn't seem to get that Canadians like being Canadians, and being a Canadian is such a myriad of things, only one of which is not being American. We have our ways, which may not be significantly different than Americans', but enough different that it feels Canadian to us.
Chrétien knew this. It was not just his fault or the fault of the PMO and Cabinet there was a rift between Washington and Ottawa. There is a history with Chrétien, Clinton and Bush (when he was governor of Texas) with a Canadian being executed with improprieties in the investigation and subsequent trial which led to a guilty verdict and finally, death. I don't think there is too much Martin can do with Bush (or any Canadian PM) unless one bows down and kisses butt, which none of us want to see.
Regardless of what the relationship is there has always been trade disputes and will always be. The poster that said US doesn't practise what they preach has hit the nail on the head. They don't in trade or in foreign policies or even their domestic policies (Patriot Act). You cannot know what to expect with their inconsistencies.