It was the question I had been asking all the way through the UN climate talks - what is any of this actually doing to reduce greenhouse gas emissions?
You would think it would be the one question on everybody's lips at conferences designed to formulate the definitive international response to climate change.
The reality is that climate change has become an incredibly complex issue.
Clearly there is no appetite in any government for doing things the straightforward way - mandating clean energy, banning coal-fired electricity generation, clearing city centres of cars, forcing builders to adopt stringent energy efficiency standards.
All this, we are told, will "damage competitiveness".
"The further development of carbon markets can help mobilise the necessary financial resources needed for a global response to climate change, and give us a future agreement that is focused on incentives to act."
Read these words in a positive way, and you visualise a mobilisation of business might to cool the Earth while making a profit - but turn the thought around, and what you have is the acknowledgment that making money, not reducing emissions, is the priority for governments and their advisers.
You certainly have an explanation for why the majority of the debates and conclusions here avoid any mention of reducing emissions.
All the jargon and complexities were too much for Sharon Looremetta, a Maasai woman who works for the charity Practical Action.
"Fine, we can have Western countries coming, but some came here with their own agenda, to protect themselves and their economies; others came here as climate tourists who wanted to see Africa, take snaps of the wildlife, the poor, dying African children and women."
Her speech brought a standing ovation from delegates.
It also brought a tart response from the leader of the European Union delegation, Finnish Environment Minister Jan-Erik Enestam, who declared: "We have proved we are not 'climate tourists', but are serious about taking action on climate change."
Busting the jargon
So let us look behind the jargon of COPs and COP/MOPs and SBSTAs and Ad-hoc Working Groups and Joint Implementation and Base Years - believe me, I could go on - and look at what the Nairobi talks actually agreed.
The headline outcomes include:
a less than firm commitment to begin negotiations on further Kyoto Protocol emissions cuts in 2008, and no target date for concluding them - despite an acknowledgement that emissions need to fall by about 50% in the near future
a decision that the protocol has been reviewed at this meeting, as its original wording demanded - many of us must have missed the review when we blinked
a commitment to have a full review in two years' time
an extension of work on technology transfer to the developing world, but only for a single year, which brought condemnation from the Chinese delegation
agreement that Belarus can enter the Kyoto Protocol's trading mechanisms in a way which could allow it to make money without reducing emissions; this decision will have to be ratified
a decision that carbon capture and storage (CCS) projects should not yet be eligible for money from the Protocol's Clean Development Mechanism
agreement that the Adaptation Fund, a pot of money to help developing countries adapt to the impacts of climate change, should be primarily under the control of developing nations
Away from the main negotiations, a number of other initiatives were announced, the most striking being a UN fund to build capacity among African governments, enabling them better to bid for clean technology projects and protect against climate impacts.
Up the command chain
Governments are generally represented at these gatherings by environment ministers - relatively small hitters on the political stage. Environmental groups have bemoaned this for a long time, and believe it could partially account for the low manifestations of political will.
But the Stern Review had clearly caught the attention of many delegations, and Hans Verolme, director of global climate change at the environmental group WWF, believes that might help to bring in some political big hitters.
"I think heads of government will get involved," he said.
"Chancellor Merkel has indicated she will take [climate change] forward in the G8, and I would expect heads of state to maybe come to the next [UN] climate summit in Bali and say. 'Let's get on with this, let's take some real action'."
The biggest hitter of all is, of course, US President George W Bush.
His disdain for the Kyoto process is the single biggest obstacle to achieving a new round of global emissions targets.
Not according to Jonathan Pershing, director of the Climate, Energy and Pollution Programme at the World Resources Institute in Washington DC.
He sees no chance of a sudden conversion, but believes the Democrat majority in Congress will initiate moves to prepare for international re-engagement should the next president prove to be less iconoclastic on climate issues.
"We've changed all the [Congress] committees' heads, and they have significant influence in the policy debate," he said.
"The new head of the environment committee, Senator Boxer from California, says that we managed to change the shape of the defence policy with Mr Rumsfeld leaving, so perhaps we can have an equally large effect in the near term on climate policy."
So in two years, perhaps, negotiations on another round of emissions cuts beyond the existing Kyoto Protocol targets may begin.
Let us invent a hypothetical target which governments might adopt, of cutting emissions by, say, 5% from 2006 levels by some future date.
At current rates, emissions will have risen by nearly half that amount by the time they even start talking.
That is a measure of the disconnect, acknowledged by many, including Britain's environment secretary, between the scientific imperative and the political process. It is also the reason why the forbidden question needs to be asked again and again and again.