There was so much politicking on Tuesday, a story slipped out in the late afternoon almost unnoticed.

"Military travel issues resolved", reported the BBC.

The ministry of defence had admitted it was all a misunderstanding on its part. The protocol contains an exemption to the military equipment requirement in the EU customs code, so paperwork had never been necessary.

The ministry failed to spot this and instructed its officials to submit declarations. The UK never raised the issue at the implementation committees.

Now both sides were truly as bad as each other. London had been as cavalier as Brussels in handling Northern Ireland with care - impeding its own army was a mistake every bit as extraordinary as the EU blocking medical supplies.

In fairness to the UUP, it had said all along the fault probably lay with UK defence officials. However, the assumption was that they had rolled over to a maximum interpretation of the protocol, rather than simply not reading it.

After the EU triggered article 16, the British government's restraint was widely praised. Might it have been tinged with sheepishness?