Blunt, informed and outspoken, this constitutional lawyer, author and blogger has emerged since the 11 September 2001 attacks as one of America's foremost critics of the "war on terror" and the resulting restrictions on civil liberties. In recent months, Greenwald has documented numerous abuses of power by the Obama administration in the name of national security - from targeted assassinations of US citizens to the authorisation of indefinite military detention.
He pulls no punches in his near-daily attacks on liberal supporters of the president. "So many progressives were misled about what Obama is and what he believes," he once wrote on his blog at salon.com. "But it wasn't Obama who misled them. It was their own desires, their eagerness to see what they wanted to see rather than what reality offered."
Indeed, what makes Greenwald so unusual, so important as a progressive pundit and polemicist, is his willingness - even enthusiasm - to denounce the excesses of Republicans and Democrats alike.
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