I presume they're thinking any potential adversaries have functioning intelligence agencies, so something as public as a launch is sufficient. No need to come out and explicitly state it.

If I, some rando on the internet, can theorize "that sure looks like it could be turned into a storable icbm that could deliver a nuke to hawaii or Tierra del Fuego or anywhere else on the globe" can make that guess, then any other major world power is likely far ahead of me in analysis.

Also well known that having the institutional knowledge and technical capability to build or adapt something in a fairly short time frame is almost as good as having the thing ready to go.

> Also well known that having the institutional knowledge and technical capability to build or adapt something in a fairly short time frame is almost as good as having the thing ready to go.

This is similar to how Japan doesn't have nuclear weapons.

> I presume they're thinking any potential adversaries have functioning intelligence agencies, so something as public as a launch is sufficient. No need to come out and explicitly state it.

Exactly. This is the norm.