General Sir Richard Sherriff tells Sky News that even if Russia is defeated in the war against Ukraine, it is going to remain determined to rebuild another empire, subjugate Ukraine, and then move on to other ex-Soviet countries, like NATO members. That could mean war with Russia.
I think instability of the world at the current moment is being acknowledged by military brass throughout NATO as having the potential volatility to see current regional conflicts expand considerably. Middle East, Taiwan, NK (unlikely but a bit of a crapshoot always), Ukraine, etc. Throw in the wild card that is Trump and his rhetoric surrounding NATO and Europe combined with his embrace of Putin and Russia/dictorial aims in the US and you’ve got several things that would have you worried presently. His job is to make sure the UK is ready to address any situations that arise I think statement is more publicly acknowledging that troubled waters COULD be on the horizon.