5 years ago,I experienced the same situation with you. At that time, my hu*****and already had a much higher salary in Japan ,and my PhD supervisor is very powerful in Japan. But both of us finally choosed USA as postdocs in a famous national laboratory.
Now, my hu*****and is working in a top 10 company of Fortune Global 500; however, I'm still searching jobs after years of postdoc because my research is too fundamental, although I have more than 15 papers published.To my knowledge, it's not easy to get a faculty position with a PhD degree out of America. So if your future postdoctoral supervisor has a big name in USA and the potential job market in your major is good, it's not bad coming to USA.