Perhaps it was inevitable that Edward Snowden's revelations about National Security Agency monitoring of Europe would prompt some people to liken the U.S. government to the Stasi, Communist East Germany's notorious secret police.
Markus Ferber, a German politician aligned with Chancellor Angela Merkel's conservative government, blasted "American-style Stasi methods." And last week, pranksters armed with a long-range projector beamed "United Stasi of America" in giant letters across the U.S. Embassy's facade in Berlin.
Fortunately for two important causes - transatlantic relations and sensible political discourse - Merkel has challenged this spurious equivalency.
"For me, there is absolutely no comparison," she said in an interview with the weekly Die Zeit. "They are two completely different things, and such comparisons only tend to minimize what the Stasi imposed on the people of East Germany. The work of intelligence services in democratic states was always indispensable for the security of citizens, and will be in the future."
As Germany's first chancellor from the east, Merkel spoke with special authority. It's important, though, to understand specifically why she is right.
Stasi's methods of surveillance and intelligence-gathering - bribery, blackmail, wiretapping, infiltration and the rest - are not normal tools of democratic governance.
And it is equally absurd to suggest, as Jakob Augstein did in Der Spiegel, that "no matter in what system or to what purpose: A monitored human being is not a free human being."
The political goals and institutional context of a given state's intelligence-gathering make all the difference. In East Germany, the purpose of surveillance was to protect an unelected party that exercised a monopoly of political and economic power on behalf of a foreign military occupier, the Soviet Union.
The Communist Party's ideology politicized every aspect of life, rendering the pettiest deviations, in word or deed, threatening - and thus subject to secret official scrutiny.
Unchecked by any law, Stasi spying evolved into an end in itself. East Germany really was a "surveillance state."
Despite much rhetoric from Snowden's camp, the United States does not fit that admittedly vague description: No party holds or plausibly aspires to a monopoly on power in this country, with its centuries-old constitutional separation of powers, two-party system, free press, private sector and robust civil society. Many fault the Foreign Intelligence Surveillance Court as a pawn of the NSA, forgetting that it was one of many reforms Americans instituted in the 1970s to correct previous intelligence abuses - and how rare it is for any nation to subject intelligence-gathering to even minimal judicial oversight.
Nor does the U.S. government define the normal exercise of freedom as inherently threatening; the terrorists and other threats about which it gathers secret intelligence are not imaginary.
Given the threats to democracy, and the technological milieu from which they may emerge, the United States needs to engage in data collection on a wide scale, both at home and abroad. The issue is whether it has checks and balances to ensure that these means remain politically and legally subordinate to legitimate ends.
On that score, there's good news and not-so-good news in Snowden's revelations. So far, he's revealed no specific instance in which the NSA programs harmed any individual.
However, the expansive FISA court reading of the Patriot Act, which authorized NSA's bulk collection of telephone metadata, may have exceeded Congress' intent. The clash between NSA data collection overseas and the domestic law of countries such as Germany is a serious diplomatic issue, for which the solution probably lies in greater consultation and transparency among allied democracies.
As Merkel suggested, though, it would help if Germans "never forget ... that America is and has been our truest ally throughout the decades." Some of the same across-the-pond pundits who are griping about President Barack Obama's proto-totalitarianism today used to hail him as the world's political redeemer.
In short, even the most worrisome issues Snowden has raised amount to manageable trade-offs between liberty and security, for both the United States and its allies.
He may deserve credit for energizing the debate, but not for enabling the Stasi-analogizers, or for referring to the United States with phrases like "turnkey tyranny" and "architecture of oppression." The excessiveness of that language should be more apparent to him with each day he spends in Vladimir Putin's Russia.
Charles Lane is a member of The Washington Post's editorial board.