For the US, UK or other Western military of whatever country I find myself living in, I would do it, absolutely, without a doubt. For that matter, all Western (NATO) forces are equal – it doesn’t make any difference whether one would serve in the French, Spanish, Swedish, Hungarian or Canadian military. Everyone participates in the major events nowadays.
In any case, I doubt such a situation would ever arise again. The only country that is a conceivable threat to world safety is China. Iran is an annoyance, but not more than that. China is a different story; however, at the same time, the Chinese military lacks any serious long-distance operating capability. They don’t even have enough amphibious ships and transport aircraft to invade *Taiwan*. They could, however, be a risk to regional (though not global) stability still, especially with their ongoing provocations in the South China Sea where a clash with the Philippines is just waiting to happen.
Even though China has a giant army in terms of manpower, and some decent (though not good) equipment for some units, most of their military is 20-30 years behind the Western world at best. The only country they could conceivable threaten are the countries adjacent to them, including first and foremost Russia.
Almost forgot North Korea: another minor annoyance, but again, not a major danger.
What other country in the world would suddenly begin a war? The Arab world? Highly unlikely given their internal struggles. Russia? Pretty much out of the question. India? Their economy depends on the West. African countries? Not in their best dreams. European countries? Dream on, 1941 is gone.
It is interesting to see how Germany is once again Europe’s foremost leader, with the largest population, strongest and largest economy, and basically the leader and decision-maker of the EU. It is Germany, for example, that decides the EU’s actions regarding Greece. Is this newly re-established position of leadership a danger? In my opinion, it is not. Germany nowadays is not Germany 70 years ago. It is a normal country like any other, with the same sort of political parties found in all other countries. It has Neo-Nazi groups, sure, but so do – famously – Greece, the US, and to some extent even Israel, not to mention the UK.
Now, to conclude, it should be obvious for all to understand that any country can nowadays be brought to its knees by means of economic sanctions if only they are sufficiently strong. No country could survive a complete embargo on all trade, and being cut off from the world financially. Solely the threat of blocking any and all export from China would likely be sufficient to stop it from any sort of agressive war; millions of Chinese would immediately lose their jobs and their entire economy would collapse, leading, likely, to a massive uprising against their government.
So, really, this question is solely theoretical. It is rather unlikely to ever become practically relevant.
Now, I think I have just proven that I am bored…..