So in Google keyword tool it states the number shown under the Global column is the amount the term is searched globally in all countries and languages on Goolge.com and Local results are search volumes for the specified country and language. So if you had a keyword lets say 1 mil global 100,000 local(united states) and your targeting Google.com and your number 1 you have the potential to get 1mil visits monthly? Or because your not number 1 in google.co.uk or google.ca you'll only get 100k.... So I guess the question is if you are in a certain country is google.com redirected to your country code so In canada google.com goes to google.ca, etc. If you look at the numbers on compete for google.co.uk and .ca is doesn't seem like residents of those countries are redirected. But anybody know for sure.
you have indeed potential on 1mil visitors.however you have to rank in all countries, ad all people that search on your keyword have to click on your site aswell and not on your competitor
The 1 million / 100 000 .co.uk /.ca is how many searches are performed monthly. You have approx 53% potential clicks of that 1 mill / 100 000 Approx 53% of searchers click the first position. No matter where you access Google either it be .ca/.co.uk they usually direct you to your country's google database, but you can choose on the lower right side to go to google.com so you can't always assume that a searcher is searching from a specific Google as everyone has a choice where to search. I am in Canada and get directed to .ca but I choose to keep default on .com as most of my customers rank on worldwide search which is .com