A look at the timeline is instructive.
Key would still have been savouring his success in hosting Xi Jinping on his first visit to New Zealand as president of China when the threat to contaminate prized NZ infant formula with 1080 landed.
The Government and Fonterra had high hopes that a successful Xi visit would draw a line under the reputational fallout from the false botulism affair, its impact on the NZ dairy industry and its prime customer - China.
But four days after Xi left Auckland for Fiji the threatening letter - along with a sample of 1080 contaminated milk powder - landed on Fonterra CEO Theo Spiering's desk.
Said Key: "The moment that the head of Fonterra got that letter ... the literal day he got it, he rang the head of the Department of Prime Minister and Cabinet - I think I was told very shortly after that. In reality, while the probability of this being a hoax is extremely high and the probability of it ever being carried out is minutely low, it's just not an option unfortunately for the Government to close its eyes and pretend it's not aware of it."
This week Key was forced to spell out what should have been blindingly obvious, when Peters alleged the Government had chosen to make the threat public four months after it was received to "distract people" during the Northland byelection campaign.
It's a nasty allegation. And one that Peters knows will strike a chord with those New Zealanders who view Key's every action as highly calculated for political effect. It plays into the NZ First leader's agenda to wrest the Northland seat away from National Party incumbency and "send a message" to Wellington through a Peters' victory.
Key may be occasionally cynical. He is a politician. But he is speaking the truth when he says that the delay in informing the public was due to the need to ensure that there were adequate systems in place for testing infant formula powder for 1080; that the supply chain for infant formula was secure and that mothers - both within New Zealand and also China - were not alarmed by an announcement that there had been a threat to contaminate infant formula without the authorities being able to give a simultaneous assurance that testing had occurred and product was safe.
There are good reasons for New Zealand to act with care when a food safety issue arises that could impact trade with key international partners.
Even though the "botulism scare" turned out to be a false alarm, it had a serious - although transitory - impact on the bilateral relationship with China.
Key had to go to Beijing to give assurances to Xi on the quality of NZ's food safety systems.
There was also added complexity in that the Fonterra threat letter landed just a fortnight before the report into the Government Inquiry into the whey protein concentrate (WPC) contamination incident was unveiled.
That report was critical of Fonterra's actions during the whey protein incident (false botulism affair). It also pointed up the need for the Ministry of Primary Industries to improve its processes on the food security front.
Disclosing the threatening letters at a time when Fonterra and MPI were still licking their wounds would have been damaging.
Where it does get tricky is that other industry players did not find out until February that the letters existed. Some of those players believe the Government should not have gone public as not only would it give rise to undue concern but it would also encourage copycats.
It's a tricky issue, but Labour's Andrew Little - in another demonstration of the maturity he is bringing to the role of Opposition leader - has defended the four-month delay.
The Peter's plot scenario would have made much better viewing than the third season of House of Cards. But Key is living in the real world. Not Frank Underwood's head.
