The Past ...
Germany began gathering information on its citizens in 1920 under the Abwehr, the German military intelligence organization. The original purpose of this organization was as a defence to domestic and foreign espionage, which continued to exist after the end of WWI*.
Shortly after the National Socialist German Workers' Party gained power in 1933, they obtained existing lists of citizens (with personal information) from the Abwehr and set out to update and expand what they could learn about their citizenry. This, of course, was a preliminary step toward their ultimate purpose in extracting from their population those the Nazis deemed "undesirable". By March 1933, not two months after taking power, they began using their lists to tear Jews and Gypsies from their homes and camps.
The terror engendered by the tactics used by the Nazis** triggered both "informing" and "hiding away", but, eventually, any form of resistance became but a trickle***.
... Becomes Prologue
The information demanded by T***p's vice chair of the Presidential Advisory Commission on Election Integrity, Kris Kobach, extends beyond what even Germany's lists contained. In the "wrong hands"****, this information can be devastating to the Nation and each individual citizen, T***pet or anti-T***per.
Especially for so many who already mistrust the government, allowing the government--even a T***p government--to have so much information basically means the government "owns them". Is T***p to be trusted never to use that information to get what he wants? He has proven to have coerced, pressured and extorted in the past; does any T***pet believe he has changed or that his "loyalty" to his base would outweigh his desire to get something from them they do not want to give up?
The Future ... ?
While the crimes committed by Nazis against its non-Aryan people may not go to that extreme, here, it is clear from T***p's, and many of his closer advisers' rhetoric and printed ideology, that the info might be used to "target" certain groups of people based on "past trends" and "future probabilities".
That any type of "targeting" may be used is troubling. That "targeting" may be against those wanting to exercise the vote is disturbing. That groups of people could be "targeted" for other purposes is alarming. And that parts of the information is said potentially to be made available for public use, without the permission of those involved, is both shocking and intimidating.
Is it any wonder that comparisons to Nazi Germany are being raised?
*While an armistice was signed ending the war, it did not end the distrust between and among the signature nations. Germany, especially, was believed to be preparing for re-arming so as to "pick up where they left off". In fact, under the agreement, Germany was disallowed from having any intelligence organizations, which had been used to determine the weaknesses of their opponents and advise in military matters.
**Those taken were, at first, done in secret and under cover of darkness. But, once "informants" began revealing information about some the Nazis missed, the abductions became very public and in broad daylight, so as to intensify the terror and increase the motive to inform.
***Incidentally, while gun control restrictions existed since 1928 (previously, all Germans were denied guns under the Armistice, though it was rarely enforced), they were seldom enforced. In 1938, the restrictions became less onerous, except for Jews, who were denied all weapons including knives. Prior to then, "undesirables" were denied weapons, but it was locally controlled.
****While Kobach claims the list will be kept with the "highest security", since even the CIA was hacked and T***p has expressed absolutely no interest in preventing further Russian hacking, how can anyone feel "secure" about anything the government has about them?