Whats interesting about the national health care issue is that more and more CEO's in the US are looking at national health care as a solution to their problems especially regarding retiree health care. The financial liabilities are staggering. Shifting these liabilities from the private sector to the public sector would be a boon for many companies (think about GM and the $1,000-$1,500 added cost per vehicle to cover employee/retiree benefits). Competitivness would improve, sales would go up, and executive pay would sky rocket as market share gains and stock prices rise.
The challenge of applying universal coverage in the States (in my opinion) is population. While residents of Canada and the UK might be thrilled about their health care systems, Canada has 32,000,000 residents and the UK has 60,000,000 residents while the US has 300,000,000 residents. Whatever challenges Canada and the UK had in implementing and operating their health care systems, the US will have 5-10 times those very challenges plus a number of challenges that are uniquely American.
On a personal level, I do have outstanding coverage through my employer (for now anyways). I doubt that the level of care I enjoy today would stay the same, much less improve, if national health care were implemented. For that reason I am skeptical about national health care. Perhaps if the plan were implemented in a manner that everyone from the President to local City Council members and from Bill Gates to the homeless guy living under a bridge somewhere all had to use the same system (fill out the same forms, stand in the same lines, recieve the same great or crappy care depending on points of view), I might get on board. Otherwise the health care system in the States would stay the same except far more people would be recieving less than adequate care (including me) while the haves and the connected would scarcely be aware that national health care even existed.