Blanket statements such as the above provide a poor basis for setting a premise, much less for establishing a conclusion.
There have been plenty of events over the past few dacades that can rightly be compared to the historical events and policies that led up to, and facilitated the atrocities that occurred during WW-II.
I have seen that quasi-argument on the internet many times, and it is invariably intended to silence the opposition rather than present a coherent counter-argument.
It is a fact that acts of government killing civilians in NAZI Germany started with small numbers of special cases and incrementally grew to several millions. It is a fact that the militarization of their police passed several warning thresholds before Germany was a full-blown police state. It is a fact that the government and society of Germany was incrementally transformed into its notorious state of tyranny through several critical events and subsequent procedures.
It is extremely foolish (and contrary to the evidence of recent years) to imagine that such evil intent no longer exists among human individuals and groups.
Nazi Germany references are only an "automatic loss of debate" when they're totally inappropriate. But in the midst of a euthanasia discussion, there are few other historical examples to use, which should be a warning signal in itself. The cult of physical ideal is the thread that is common to both cultures, and in both situations the result is that those that don't meet that ideal are considered to be less than human, their lives not worth living. Also there are some very specific parallels, for example, "Million Dollar Baby" and "I Accuse" performing the exact same propaganda role.
There is less than zero correlation between pre-war Nazi Germany and Hitler's rise to power, with most posters on FR's, replies and/or the way Jeb handled the Terri case. As a matter of fact, many of those who were screaming FOR Jeb to send in STORM TROOPERS TO SAVE TERRI were closer to Nazis, than the ones whom they were labeling such.
You may have an early sign-up date, but it would seem that you are in the dark about the net rule, that once someone likens another poster to Hitler, they've lost the debate and THAT is what I made reference. So now you know; "blanket statement" my Aunt Fanny !