A few thoughts on Healey's departure.
At the end of the day, the root cause is a failed defence review process. The review proposed things on the basis that spending would rise to 2.5% of GDP by 2027, a relatively modest pace of growth that was & is incompatible with everything the UK wants to do—GCAP, AUKUS, a strategic reserve corps for NATO on land, carrier strike & more munitions/readiness.
The gov't was unwilling either to make choices among these, which would have been politically and diplomatically painful, or to spend *significantly* more in the short & medium term, instead pointing to non-credible commitments out into the mid-2030s. There was and is no credible path to the 3.5% of GDP target by 2035 that the PM publicly agreed at the Hague last year.
Now the UK is going to go into the Ankara summit in a weak position, with a teetering government, and with a likely successor to Starmer who is no more likely to support higher defence spending, all with predictable consequences for the US-UK relationship.