In December 2010, in the chaotic weeks following WikiLeaks' release of hundreds of thousands of diplomatic cables, a loosely organized network of hacktivists calling themselves Anonymous launched a series of distributed denial-of-service attacks that temporarily brought down the websites of MasterCard, Visa, and PayPal — the financial companies that had cut off payment processing services to WikiLeaks under what appeared to be pressure from the US government.

The attacks, dubbed "Operation Payback," marked one of the first major tests of a new form of political activism: the use of coordinated cyberattacks as a protest instrument. For a few days, millions of ordinary customers found themselves unable to access financial services — collateral damage in a battle between a stateless media organization, the world's most powerful government, and a distributed network of volunteers with varying technical skills and wildly varying motivations.

The legal and ethical questions the episode raised were genuinely complex. WikiLeaks' supporters argued that the payment processing cutoff amounted to extrajudicial censorship — corporations acting as enforcement arms of government pressure without any court order or legal finding. Critics of Anonymous countered that DDoS attacks were simply vandalism, inflicting harm on bystanders to make a political point.

Julian Assange, under house arrest in Britain at the time, became a focal point for debates about press freedom, government secrecy, and the internet's relationship to both. The WikiLeaks saga would continue for years, but the December 2010 financial blockade and the hacktivist response marked a pivotal moment in the emerging politics of digital information.