The Reason to Sell the Yen Has Changed — and 160 May Not Be the Floor

This analysis flags a quiet but crucial shift: the reason markets sell the yen has changed engines. The old driver was the expectation of an ever-widening US-Japan rate gap; the new one is the gap in policy pace — not a bet that the BOJ will stand still, but that it moves too slowly to catch up with tighter Western central banks. That distinction matters. If weakness is purely about rate differentials, a dovish US turn could spark a fast yen rebound; if it is about the BOJ lagging, the yen stays weak even as the US eases. Like three cars on a highway, the US and Europe hold high speed while Japan accelerates too gently and falls further behind; capital crowds toward the faster vehicles. Since 2024, as the BOJ exited negative rates, the market's yardstick evolved from 'will it move' to 'is it moving enough' — so an undersized hike can paradoxically reinforce the weakness. For readers, the takeaway is to update the yen compass from 'rate gap' to 'policy-pace gap': when the BOJ meets, the real question is no longer whether it hikes, but whether it hikes enough.