Under the Protocol the UK government is responsible for applying checks on goods entering NI from the rest of the UK to ensure that goods destined for the Republic of Ireland meet EU regulations. This is to avoid a "hard border" between the Republic and NI - i.e. avoid any need for checks at the land border.
Article 16 of the Protocol states that "if the application of this Protocol leads to serious economic, societal or environmental difficulties that are liable to persist, or to diversion of trade, the Union or the United Kingdom may unilaterally take appropriate safeguard measures. Such safeguard measures shall be restricted with regard to their scope and duration to what is strictly necessary in order to remedy the situation. Priority shall be given to such measures as will least disturb the functioning of this Protocol."
It may be noted that "or diversion of trade" is a separate clause. It is not "serious diversion of trade which is liable to persist" but just "diversion of trade".
"Diversion of trade" has a recognised meaning and is specifically related to customs checks and restrictions. If additional barriers are erected on trade route A, that results in less trade through A and more trade through trade route B so that there is a "diversion of trade".
In the months since the Protocol came into force there has been diversion of trade, particularly in the case of agriculture and food, with many Northern Ireland businesses switching suppliers from those elsewhere in the UK to those is the Republic of Ireland because goods can be transported across the land border without any checks whereas goods arriving in NI from the other side of the Irish Sea are subject to checks which add to expense and delay.
There has been significant disruption to longstanding trade flows between Great Britain and Northern Ireland, and a significant, measurable increase in trade on the island of Ireland. The value of Ireland’s exports of goods to Northern Ireland is trending far above historical levels in 2021: up by nearly 40% this year compared to the same period in 2020, and by more than 50% on the same period in 2018. Some sectors particularly susceptible to that diversion, such as food and pharmaceuticals, have experienced even stronger growth. Meanwhile, as set out above, surveys continue to underline the disruption being caused to business with Great Britain, with movements of specific commodities (such as chilled meats) seeing particular impacts.
Northern Ireland Protocol: the way forward, July 2021, CP 502 p.29
This diversion of trade has happened notwithstanding that we are currently in a "period of grace" before the customs checks required by the Protocol have been fully implemented.
The appropriate safeguard measures which a party is entitled, under Art 16, to unilaterally apply are restricted with regard to their scope and duration to what is strictly necessary in order to remedy the situation. So a party acting unilaterally cannot go beyond what is strictly necessary but it can do whatever is strictly necessary to remedy the situation - "remedy" not just ameliorate.
It seems clear that the diversion of trade condition in Article 16 is bound to arise almost immediately from the implementation of the customs checks which the Protocol requires so that the agreed terms are apparently self-defeating i.e. in respect of every class of goods implementation of the checks which the Protocol requires immediately leads to conditions which entitle a party to unilaterally give notice that it will not carry out the relevant checks which the Protocol would otherwise require on that class of goods.
Generally you expect a treaty to commit the parties to carry out actions for a number of years. There will often be clauses allowing for derogation in certain circumstances but they will be circumstances which the parties think unlikely - but not zero risk hence the need to build in a safety valve. If a clause allows derogation in circumstances which are quite likely (but not certain) then the treaty still may be perceived to have some effect. But if you had a clause allowing derogation in circumstances which are actually the inevitable consequences of actions which the treaty requires, the terms would then appear to be be self-defeating.
Am I missing something here? Is there a possible reading of the diversion of trade terms of the Protocol which would mean that the diversion of trade* terms are not inevitably "self-defeating".