When historians look back at the first few decades of the 21st century, 2013 will almost certainly be seen as a game-changing year. That judgement can in the main be attributed to a series of disclosures made by American fugitive Ed Snowden, formerly a low level CIA employee and National Security Agency sub-contractor whose flight and subsequent revelations have given rise to sensational reverberations across the globe.

On Tuesday, the world woke up to a new missive from NSA whistleblower Edward Snowden, and no one quite seemed to know what to make of it. In an open letter to the people of Brazil in that country's Folha de S. Paulo newspaper, Snowden appeared to make a subtle appeal for asylum from the Brazilian government -- and maybe hinted that he would help Brazil fight back against NSA surveillance in exchange for their protection.

Alarmed by large-scale spying on their state-owned oil and mining firms and monitoring of personal communication of their top leaders and bureaucrats by the U.S. National Security Agency (NSA), South America’s two biggest countries are urging all other countries in the region to form a joint cyber shield to deflect such surveillance. The move, led by Brazil and Argentina, is the first such effort by a group of countries since NSA revelations about mass surveillance began to come out in June.

Spy agencies across Western Europe are working together on mass surveillance of Internet and phone traffic comparable to programs run by their US counterpart denounced by European governments, Britain's Guardian newspaper reported on Saturday. Citing documents leaked by fugitive former US National Security Agency (NSA) contractor Edward Snowden, the Guardian said methods included tapping into fibre optic cables and working covertly with private telecommunications companies.

Unsurprisingly, the news that the NSA has been monitoring the calls of dozens of world leaders hasn't gone down particularly well with any of those world leaders. In fact, after suspecting that the US might have been snooping on her communications, last week German Chancellor Angela Merkel rang up Obama herself to demand some answers. A couple of days later, it emerged that her phone has potentially been monitored for more than a decade by the supposedly friendly American government.

For presidents, like sports-team managers, the tough weeks tend to outnumber the jubilant. But even by the standards of an unforgiving job, Barack Obama could be forgiven for feeling unusually buffeted of late. Many of the blows have come on the domestic front, with the all-consuming stand-off of the government shutdown segueing into frantic efforts to defend and repair the roll-out of Obamacare amid charges of fatal technological incompetence.

A series of events in recent weeks has created a widespread narrative that the U.S. is an unreliable ally and a weak partner. First, the U.S. government shutdown forced President Barack Obama to cancel his trip to a couple of Asia summits. Then, new Edward Snowden leaks revealed that the National Security Agency has been spying on up to 35 world leaders, including top U.S. allies like German Chancellor Angela Merkel.

The U.S. government seems outraged that people are leaking classified materials about its less attractive behavior. It certainly acts that way: three years ago, after Chelsea Manning, an army private then known as Bradley Manning, turned over hundreds of thousands of classified cables to the anti-secrecy group WikiLeaks, U.S. authorities imprisoned the soldier under conditions that the UN special rapporteur on torture deemed cruel and inhumane.