Under changes already implemented, for example, it is now impossible for a single person to take classified information off a government computer.
The White House said today the release of the sensitive U.S. government information could not only embarrass the United States and other governments, but could put Americans and human rights activists around the world at risk.
"By releasing stolen and classified documents, Wikileaks has put at risk not only the cause of human rights but also the lives and work of these individuals," the White House said in a statement released today. "We condemn in the strongest terms the unauthorized disclosure of classified documents and sensitive national security information."
The government had been bracing for the worldwide fallout feared from the release for days, preemptively warning allies in the hope of lessening the blow after the classified documents went public.
Some of the documents were leaked to The New York Times, The Guardian in the UK and France's Le Monde, in advance of a full posting on the WikiLeaks site.
Members of Congress from both sides of the aisle condemned WikiLeaks' decision to release the material.
Sen. John Kerry, D-Mass., chairman of the Senate Foreign Relations Committee, called it "a reckless action" that will not only complicate U.S. diplomatic efforts, but could put people's lives at risk.
"This is not an academic exercise about freedom of information and it is not akin to the release of the Pentagon Papers, which involved an analysis aimed at saving American lives and exposing government deception," he said.
"Instead, these sensitive cables contain candid assessments and analysis of ongoing matters and they should remain confidential to protect the ability of the government to conduct lawful business with the private candor that's vital to effective diplomacy," he said.
Rep. Pete Hoekstra, R-Mich., the incoming Chairman of the House Intelligence Committee, said Wikileaks is "undermining American foreign policy" as America's allies "are forced to question whether the United States can keep secrets" and diplomats are forced to "try and patch foreign relations strained by this illegal leak."
It is an embarrassment to the Obma administration, he said.
"Wikileaks clearly is determined to undermine U.S. national security and damage our foreign relations," he said. "The disclosure of thousands of potentially classified cables and other documents is an embarrassment to the Obama administration and represents a critical failure by the Pentagon and intelligence community to protect sensitive national security information."
WikiLeaks has said the release would be seven times the size of its most recent leak, in October, which contained about 400,000 Pentagon documents about the war in Iraq. WikiLeaks also published roughly 70,000 documents in July about the war in Afghanistan.
Senior U.S. officials have warned that the WikiLeaks documents posted today would be considerably more damaging than the two previous WikiLeaks document dumps.
"This is outrageous and dangerous," a senior U.S. official told ABC News. "This puts at risk the ability of the United States to conduct foreign policy. Period. End of paragraph."
The chairman of the Joint Chiefs of Staff also weighed in Friday, telling CNN he hoped these kinds of leaks will eventually be plugged.