Success, it has been said, has many fathers while defeat is an orphan.

As world leaders headed to the airport after the Toronto G20, it was clear that the many fathers of the group that now bills itself as "the premier forum for our economic co-operation" were all eager to declare their summit a success.

Even if those success claims were for different reasons.

As host, Prime Minister Stephen Harper was, probably by necessity, the most general in his assessment: The agreements set out in the final communiqué, he said, were "important steps that Canada was seeking."

U.S. President Barack Obama said his country achieved all three of its main goals (to make sure the global recovery is durable, to continue reforming the financial system and to keep the pressure on a range of global issues).

While British Prime Minister David Cameron claimed success at achieving his three goals, which were different from Obama's.

The most important for Cameron, it seems, was to secure international approval of his recent austerity budget, which contains a tax on banks.

So, five things to note from reading between the lines of the G20 communiqué.

To each his own

One. On the big issue of whether to maintain government stimulus to create jobs, or to cut spending to contain deficits and debt, there was no agreement.

Canada's Stephen Harper and U.S. President Barack Obama getting ready for the G20 group portrait on Sunday, June 27, 2010 in Toronto. (Fred Chartrand/Canadian Press)

The communiqué says countries should "follow through on fiscal stimulus" while working on "growth friendly fiscal consolidation plans."

That means countries can do whichever they think meets their own particular circumstances. (Or try to have their cake and eat it, too.)

They did agree to halve the size of their deficits by 2013 and to stop total public debt increasing as a percentage of GDP by 2016.

No word on how to do that, however. Apparently it is to each his or her own way. And slumping Japan has been given a pass from meeting these targets at all.

Work in progress

Two. The promise to "strengthen" the global financial system is getting considerable attention from the International Monetary Fund, the World Bank, the Bank of International Settlements and so on.

The problem is that the work they are doing is not yet complete.

So the key questions of how much capital banks must keep on hand to cover potential losses, and the way that capital is calculated so that it can be converted quickly into cash if needed, have been passed forward to the next G20 summit in Seoul in November.

All that has been agreed so far is that banks will have to keep more capital on hand and it must be of greater "quality" than previous standards in most countries.

But the final plan will likely not take effect until 2012, three and a half years after the financial meltdown that lead to the Great Recession.

Climate change

Three. Prime Minister Harper originally claimed environmental discussions would be a minor part of the summit.

French President Nicolas Sarkozy, right, Russian President Dmitry Medvedev, left, and German Chancellor Angela Merkel talk privately during the G20 Summit in Toronto in June 2010. (Eric Feferberg/Associated Press)

That reflects Canada's ambiguous approach to global warming at a time when Harper is billing us as "an energy superpower."

But lobbying by the UN secretary general as well as by Mexican President Felipé Calderon, who is hosting the next UN climate change conference, resulted in a number of environmental mentions.

For Canada, the most significant is the renewed pledge of G20 countries to phase out "inefficient fossil fuel subsidies in the medium term."

That means that countries that give tax breaks to oil companies or coal miners, or countries that subsidize fuel for consumers, will have to eliminate those incentives by 2020.

What that means for Canada, with its vast reserves of oil sands and its large array of provincial incentives for drilling and extraction, isn't entirely clear.

But it has to be noted that President Obama, whose country is the biggest destination for Canadian oil and gas, mentioned the phase-out plan approvingly in his closing statement.

International trade

Four. There is another potential problem for Canada in Sunday's final communiqué.

The document renews the pledge to try to complete the Doha Round of international trade negotiations, which have been stalled for at least four years.

The Doha pledge has been in every G20 statement since the first leaders' meeting in Washington in 2008.

But at his final news conference, Britain's David Cameron said that, to try to break the negotiating logjam, the leaders agreed to put more items for debate on the agenda. The idea being that with more things to talk about, there should be more possibilities for deals and trade-offs.

For Canada, that likely means that our supply-management system for dairy products, which is so important to Quebec, could come under renewed attack.

Canada's refusal to open our market to dairy products from other counties is already seen as a big stumbling block.

The Group of Two

Five. The weekend meeting also gave us a glimpse of the real power dynamic upon which much of the world economy now turns.

For all the talk of the G20 representing the world economy as it really is, what we really saw was that there is a G2 and 18 or so others.

Those two countries, of course, are the United States and China.

China holds a great deal of American government debt at low interest rates. America buys much of the goods China makes to fuel its export driven economy, as it keeps its exchange rate artificially low so those products are cheap for American consumers.

The result is a huge American trade deficit with China.

To deal with this problem, Washington has been pressuring China, at summits like the G20, to let the value of the yuan increase and sell more Chinese manufactured goods internally.

To head off criticism, the Chinese announced just before the Toronto G20 that they would let their currency appreciate. But they didn't say by how much.

The final communiqué, however, hinted that this increase should be significant and in his closing statement President Obama was blunt. Without specifically mentioning China, he said: "No nation should assume its path to prosperity is paved with exports to America."

In the end, the world's self-proclaimed "premier forum" for economic co-operation left Toronto with more questions than it answered.

But enough was at least kept in play by what is truly a very diverse group that it can fairly be said to have been a success.