It has always been my belief that high-energy physics and other forms of scientific, technological, and economic competition among nations is a good substitute for war at a tiny fraction of the costs. CERN has become a veritable "scientific United Nations" of young people speaking a hundred languages (but mostly French and English), with a common purpose: to figure out how nature works and be the first to tell the world.
Other nations, particularly European, strongly support their young people and their education in all areas, in particular in science. In sad contrast, we have squandered roughly $1 trillion on unwinnable wars, with no end in sight, while an Iowa high school physics teacher is given only a pittance for supplies for the year. We must be building solar and wind generators, developing non-petroleum liquid fuels and, yes, finding out why the proton has mass.
I would even say that a typical physicist, especially in North America, Europe, Japan, etc. have more "international experience" than just simply being able to "see Russia from my house". It is very common for physics majors to encounter students from all over the world. Here in the US and especially in smaller physics programs, it is not unusual to see more international students majoring in physics than US citizens. So there is definitely a very large international flavor in physics. A typical physics major would have encountered, and hopefully made friends, with several people from various parts of the world. That, to me, is a tremendous international experience.
Such diversity continues into the profession itself. Go to any major conferences such as the APS March and April Meetings. Without any international participation, the conference would be half-empty and major scientific contents would be missing. The international collaboration and friendship established within physics should not be underestimated.