It's about #10 overall, but most of the countries above it are tiny, and their overall production is negligible.
Canada and Australia do appear above the US on the list, though not radically so. They are somewhat smaller than the US.
Although the US is not literally #1, either overall or per capita, it's one of the best targets for reducing CO2. Its per-capita consumption is so much higher than most that it should be able to look to other developed countries for ways to reduce it, and its overall consumption is so high that any small change will have a disproportionate effect on the total.
That's a lot more words than saying "The US is the largest per-capita producer", but arguing that it isn't is really just arguing over details. The important question is "Who should be taking the biggest steps to reduce CO2" and the answer is unambiguously "The US", followed by China and the developed Western countries.
