Wrote 'Chaos Monkeys' (http://amzn.to/2ow1CHE ). Formerly @facebook, @ycombinator. גם זה יעבור 
You can add location information to your Tweets, such as your city or precise location, from the web and via third-party applications. You always have the option to delete your Tweet location history. Learn more
It matters to any US citizen that wants to go to those countries for business or leisure, so it matters to the US
Most Americans don't even have passports, much less regularly travel to places like Europe. It'll be an elite concern at best, and I have trouble imagining anyone making a national issue out of it.
It will be a concern of business lobbies, the travel industry, immigrants with family abroad etc... I think they will have to work out a system
Twitter may be over capacity or experiencing a momentary hiccup. Try again or visit Twitter Status for more information.
