Ah yes, very good point. Only been overseas a couple times. Though some of the designs I've worked on have probably ended up in the very car you're driving. I've been in the industry for about 6 years total now (on and off, so really maybe 3.5 years solid).
I don't think you can ever bail on all the knowledge you've acquired, but it can easily be applied to other areas outside of engineering.
It sounds like you definitely know your stuff and continue to enjoy the passion for engineering that I lost a while back. I'd much rather depend on products designed by someone with your enthusiasm than those designed by the majority of people I know who are just going through the motions. Good luck in your career!