By Nick Assinder
Political correspondent, BBC News website
It started as a debate over the likely impact on jobs of the replacement, or otherwise, of the Trident nuclear system.
Claims that Trident decision has already been made
But, with CND and Greenpeace giving evidence to the defence committee of MPs, it soon turned into a row over whether there was a government "conspiracy" over the issue which had already seen Tony Blair giving the go-ahead for a new generation of warheads.
And, as the debate over the future of Britain's independent nuclear deterrent rumbles on, it is a row that is certain to be re-enacted time and again.
There have already been claims that both Mr Blair and Gordon Brown have, in effect, pre-empted any Commons vote by announcing their support for a replacement of the Trident system.
It was the chancellor's brief reference to his support for a continuing deterrent that led some left-wingers, led by Clare Short, to withdraw their support for him as next Labour leader.
In fact, Mr Brown's remarks - that he favoured "retaining our independent nuclear deterrent" - leave some room for manoeuvre.
In any case, MPs have now been promised a say in the issue, although it remains unclear whether they will get the free Commons vote many are pressing for.
But this "conspiracy" goes beyond claims the prime minister has already made his mind up and is determined to get his way.
CND claim Britain is breaching non-proliferation treaty
CND chairman Kate Hudson believes the amount of investment, recruitment and development being carried out at the Aldermaston Atomic Weapons Research Establishment is evidence that the prime minister has already given the green light for production.
"It suggests the decision to go ahead with a new generation of nuclear weapons has already been taken," she said.
And that amounted to a British breach of then international non-proliferation treaty.
Ms Hudson was immediately accused of indulging in conspiracy theories.
Some MPs on the defence committee pointed out the government had been open about the maintenance and development work being done at the establishment.
Durham's Kevan Jones told her: "You are trying to portray some great conspiracy, which it is not".
The simple explanation, she was told, was that work needed to be done to maintain the existing weapons and in preparation for any decision to renew the weapons, or when the time came it would not be possible to carry it out in time.
That stung Ms Hudson into declaring she was not suggesting a conspiracy, which brought a number of mumblings from amongst committee members that "of course you are".
Defence minister Lord Drayson later added his voice, declaring it was a "misunderstanding" of the position. Work was being done at Aldermaston to keep the existing weapons safe, he said.
Although he also conceded this work could be used to design a future warhead, "should it be required".
Sceptics, however, continued to raise their eyebrows after Lord Drayson also confirmed that the debate on Trident would come only after ministers published a white paper - by the end of the year - setting out a series of options but offering the government's favoured option.
That has already led to claims the government is putting the cart before the horse and demands that any debate should precede its decision.
Still, Ms Hudson will get at least one more bite of this particular cherry as the committee intends to invite her back to give evidence on the non-proliferation treaty and Britain's responsibilities.