If the gang that's running this administration decides to go into Iran, the French will doubtless pee and moan about it, but they're not going to "put their foot down" and draw a line in the sand; certainly not if they'd have to do it alone. And while I'm not an expert on the former Soviet Union like world-renowned scholar Dr. Condoleeza Rice, I suspect that Putin's recent hint of saber-rattling is more of the same. My hunch is that this kind of talk is served up as sauce for the French or Russian home front and the outraged world community rather than as a serious shot across the bow to the noble admirals of our Ship of State.
I'm not sure whether the American Eagle will go shrieking with steeled talons into Iran. Certainly a sensible group of leaders, knowing what messes Afghanistan and Iraq have become and aware of the current strain on the economy and the military, would not do it. But the problem with ideologues and megalomaniacs, as the careers of Constantine, Napoleon, and Hitler show, is that it doesn't matter if their empire is a tottering wreck or if their enemy is genuinely harmless or too big a bite to chew off. They tear into it anyway because they simply cannot stop.
If the Eagle is unleashed, I think the strategy of the European nations will be to damn with fiery rhetoric while wrangling as many contracts and concessions as they can beneath the table. I don't think any of them believes the US can sustain its imperial pretensions for long; some like Putin are probably expecting to pick up the star-spangled gambler's chips after he's shot the piano player and run out the back door (I think I've stolen that from someone but I don't remember who), while nobler souls may believe they'll be able to set a better example at "winning hearts and minds" and enhance their nation's leadership on the world stage. I don't think either Europe or the UN will help the US at all, and they'll probably take advantage of any opportunity to force the US to humiliate itself with begging (as they've just done), but none of them will actively interfere or oppose the invasion.
Then again, some people believe that remarks Putin made a few weeks back imply that he might have been willing to actively support resistance to the American invasion of Afghanistan if Russia and the US had not come to an arrangement beforehand. So who can say? Maybe the big dawgs are just itchin' to have a scrap.
Françoise