President Obama and the other leaders of the Group of Eight nations gather in Northern Ireland on Monday for a two-day summit. And thanks to the latest revelations from U.S. National Security Agency leaker Edward Snowden, the already delicate conversations between those leaders will probably be more awkward than usual.

Among other things, this leak suggests that, as in sporting events, there's a home-field advantage when it comes to hosting international summits.

On Sunday, Britain's The Guardian said that at a 2009 G20 summit of world leaders in London, Britain's counterpart to the NSA, the Government Communications Headquarters (GCHQ), electronically monitored foreign delegations. The reports are based on documents from Snowden, and include some pretty interesting details, including that GCHQ and MI6 set up and lured foreign delegates into internet cafes specially rigged to record keystrokes and intercept emails, and that the Brits managed to crack into some delegates' BlackBerrys.

In this case, the point of the eavesdropping wasn't anything you'd find in a John le Carré novel. No, says The Guardian, it appears to have been set up "for the more mundane purpose of securing an advantage in meetings," which were geared toward global economics. That is, diplomatically speaking, an unfair advantage, and lots of countries will be annoyed by the report. But the only "named targets" the newspapers identifies are "long-standing allies such as South Africa and Turkey."

The Guardian also highlighted one document detailing efforts by an NSA team in North Yorkshire, England, to "target and decode encrypted phone calls from London to Moscow which were made by the Russian president, Dmitry Medvedev, and other Russian delegates." Medvedev is no longer president, but Obama will meet with Russia's Vladimir Putin this week, with whom Medvedev was likely communicating in 2009.

Matthew M. Aid, an intelligence historian in Washington, isn't that impressed with the newest leak. Snowden's earlier revelations "confirmed longstanding suspicions that NSA's surveillance in this country is far more intrusive than we knew," Aid tells The New York Times. But while the new information will remind G8 delegates to be wary, possibly thwarting new GCHQ plans, it won't surprise anybody at the conference. "This is just what intelligence agencies do — spy on friends and enemies alike," Aid says.

The document on NSA attempts to snoop on Medvedev fall into the same boat: Russia has apparent confirmation of one NSA tactic, but won't be surprised. Still, says Caroline Bankoff at New York, "while the United States spying on Russia (and vice versa) is certainly nothing new, this particular instance is kind of funny because Obama 'stressed the need to be candid' at the meeting" in 2009. And this late-breaking report in The Guardian "will likely have no effect on everyone's plans to spy on each other on Monday," she says, "but it might give protesters some new ideas for things to put on their signs."

How did an NSA contractor get hold of top secret British documents? The ones posted by The Guardian appear to be mainly PowerPoint presentations touting the GCHQ's success — are all government secrets now on PowerPoint? — and one of the slides has the logos of the NSA and Canadian intelligence, as well as GCHQ's. That suggests Snowden had access to them "under the auspices of a joint program," GCHQ historian Richard J. Aldrich tells the Times.

If nothing else, these new Snowden documents offer "a rare window onto the everyday electronic spying that the agency does in close cooperation with Britain, Canada, Australia, and New Zealand," says the Times.

But Snowden's leaks will have real consequences for Obama, and Europe, says Scott Wilson in The Washington Post. Obama's buoyant popularity among Europeans has already waned since his first year, and the NSA leaks have "angered many European politicians, particularly German Chancellor Angela Merkel, whom he will see on both stops of his three-day visit."

Germany and France are also frustrated that Obama didn't agree to arm Syria's struggling rebels earlier, Wilson says, but the NSA's internet data-collection details will likely have a concrete effect on talks over a new U.S.-European Union trade pact: "Already concerned about how and where data is stored and protected, European leaders have bristled over the NSA program, raising the prospect of restrictions on the flow of information, data-storage rules and new protections for intellectual property as part of any new trade agreement."

The NSA data harvest also feeds Europeans' disappointment that Obama may not have turned out to be a "political redeemer" after George W. Bush, Jan Techau at the Carnegie Endowment for International Peace tells The Washington Post. "Those expectations, of course, were greatly exaggerated. Soon it became clear, as it is now, that he is simply an American president with all of the ugly power politics that the position involves."

Snowden says he went rogue to warn Americans that their privacy rights are in danger by NSA overreach. As the scope of his leaks widen to U.S. — and now British — spying abroad, it seems he has a larger plan, or no plan at all.