As a European, the whole registering to vote thing is honestly one of the wildest parts of the US elections to me. It’s so unnecessary complicated and prone to errors/manipulation. I just have to show up with my ID, doesn’t matter if it’s for the EU parliament or the local city senate.
I see comments like this a lot. Most important and apparently most difficult for Europeans (and others but it's almost always Europeans) to understand is that the US is a very large country, made up of 50 semi-independent states, each with its own government and laws-- about many things, not just elections. So that's why things are more complex here--we're not a small monolithic nation with one single, centralized government and set of laws that apply to everyone no matter where in the country they live.
Each US State runs its own elections; a person obviously can't be allowed to vote in more than one state. Since people can move from one state to another at any time, and even have residences in more than one state at the same time (such as college students and well-off people), it's necessary to register with the state you will be voting in, so that you are officially able to vote in that state and no other.
update response to the replies: Funny, the replies to this post comparing the situation to that of their country with the EU is basically the relationship I was trying to explain, yet they think they have somehow refuted what I said, when actually they validated what I said. Here's what's really "wild": First you call our system stupid, then when I explain our system to you, you say, "But that's just like our system!" and then downvote me for making you realize that what you called stupid is what you also have. 😄
Read the original comment condescendingly asking "Why do you have to register to vote?" yet they are also registered to vote in their own country, but don't even realize it because it was done automatically for them as a citizen. Your government has to track who is eligible to vote[1] and therefore in EU elections as well, one way or another, even if you don't use the word "registered" for it.
BTW, Many US States also automatically register their residents to vote (though a person can optionally refuse that); other US states expect you to register for it yourself (perhaps some European countries too?). Each state makes its own laws about that. Once registered in a state, we can also vote in our Federal elections, just like you can vote in EU elections.
[1] Example: Germany voter eligibility:
Generally, to be allowed to vote in Germany, you need to be a German citizen who is at least 18 years old. You must also have been officially registered in the place where you’re voting, such as Berlin, for at least three months, and you must not be excluded from voting for other reasons (for example, if a court took away your right to vote because you were deemed legally incapable of making your own decisions).
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