The coordinated intervention was the first U.S.-Japan joint operation to buy yen since 1998.
Manuel Augusto Moreno | Moment | Getty Images
Japan yen performance year-to-date
Industry veterans told CNBC that one of Washington’s biggest concerns was avoiding a scenario where Japan would need to dump large quantities of Treasurys to finance unilateral intervention, given how the north Asian nation is the largest foreign holder of U.S. government debt.
Louise Loo, head of Asia economics at Oxford Economics, said that that was “possibly one of the key reasons” behind U.S. participation.
“There is a self-preservation element here. Volatile markets driven by potentially fiscally-aggressive policies from Japan could…