A bit far from the technology related fields, but the beef import agreements are the most explicit on this part [0]. US beef was found in clear violation of the safety rules multiple times, but Japan had to bend anyway ("The government has put priority on the political schedule between the two countries, not on food safety or human health.").

Japan is typically not doing great in its relationship with Korea or China, or even India, nor the EU really (France and Germany are closely friendly, but won't give much economic benefits), so the US have a pretty strong leverage when it comes to negociations.

[0] https://en.wikipedia.org/wiki/United_States_beef_imports_in_...

PS: there's a mountain of other reasons now, but Japan and Russia were also not doing great as they've been fighting over the northern islands for decades. To my eyes they really really suck at international relations in general.

i.e. "open up your market to us and stay silent about our tariffs on your products, or else"