Mossad kidnapped Vanunu from Italy. With or without local help, you can be kidnapped anywhere.
So really it depends where you are and what you're willing to do.
The fact this is not going off the top news makes it much harder - in all aspects (the tactic operation is just one aspect to such act).
You can't come forward against the world's most powerful intelligence agencies and be completely free from risk because they're such powerful adversaries. No one can meaningfully oppose them. If they want to get you, they'll get you in time.
This happened just two years ago. Palestinian engineer, traveling in Ukraine, was captured by unknown people, and was found in Israel prison week later.
The US government has all the time in the world and in months/years from now when nobody remembers his name there will be an opportunity for a extradition to be done quietly.