LONDON — Edward J. Snowden, the whistleblower on global U.S. surveillance, has been called all kinds of things by members of Congress over the past couple of weeks — including a “defector” and a man guilty of “treason.” Federal prosecutors have prepared a sealed indictment against him.

At the same time, he has been lauded by Julian Assange, the founder of WikiLeaks, as a member of the “young, technically minded” generation “that Barack Obama betrayed.” Assange called President Obama the real “traitor.” Across the world, and in the United States itself, many people sympathize with Snowden. They see his leaks as a needed stand for individual freedom against the security-driven mass surveillance of a U.S. National Security Agency armed with the technology to gather and analyze the digital trails of our lives.

So what is Snowden? A self-aggrandizing geek who betrayed his country and his employer, Booz Allen Hamilton, exposed the United States to greater risk of terrorist attack, and may now — wittingly or unwittingly — have made his trove of secrets available to China and Russia, nations that are no longer enemies but are rival powers?

Or a brave young American determined to fight — at the risk of long imprisonment — against his country’s post-9/11 lurch toward invasion of citizens’ lives, ever more intrusive surveillance, undifferentiated data-hauling of the world’s digital exhaust fumes (for storage in a one-million-square-foot fortress in Utah), and the powers of a compliant secret court to issue warrants for international eavesdropping and e-mail vacuuming?