Washington and Beijing are locking the agenda for the Trump-Xi meeting, and the instrument that will actually determine what Xi can concede sits at Premier Li's economic working group, not at the Pentagon's Seventh Fleet. Mei Chen has already logged the strait transit and Taipei's restrained tracking of it; the question this desk asks is what the PLA Navy's shadowing does to the PBOC's calendar, because a summit built around Taiwan is also, or more precisely, a summit built around whatever tariff resolution Li's group has been holding monetary easing hostage to since March. That resolution requires a document, not a gesture, and no document has moved.

The mainland side has one lever it controls regardless of what the Seventh Fleet does in the strait: the PBOC's open-market desk sets the medium-term lending facility rate on the 15th of each month, and it has held that rate through three consecutive fixings while Li's group waited on the tariff track. A summit that produces a Taiwan Strait line without a tariff annex leaves the MLF rate exactly where it is, because the desk does not price naval transits, it prices the trade document Washington has not yet sent to Beijing's negotiators. The September 15 fixing is the next date that desk can move on, and it will only move if the annex exists by then.