The Israelis abducted Mordecai Vananu, a nuclear scientist who revealed their secret nuclear program, somewhere in Europe and took him back to Israel in a crate for trial.
WI, at some point, the US did that to Roman Polanski?
Do you mean the FBI just sending some people to France, having them drag him to the Embassy or onto a plane, and flying him out of the country? I can't see the French government taking kindly to that.
It might depend on how it goes down, too. If anyone other than Polanski gets hurt (some policeman gets beaten up or worse by the extraction team), things probably get worse from whatever they were.
I can't really see this being done. Polanski was 'merely' a common criminal. Bad, to be sure, but not a traitor or intelligence leak. To have the US snatch him out of a foreign country, and risk a diplomatic incident over him, doesn't seem very likely.
Now, maybe some private individual manages to swing it, abducting Polanski and dumping him on the steps of the FBI HQ in Washington, but still, unlikely.