What is meant by "recognizing dual citizenship"?

An example of a mess involving dual citizenship are men born in America, for example, but of S. Korean descent who find out they are “officially” S. Korean citizens and are required by law to do military service in in S. Korea. Despite never having set foot there, applied for S. Korean citizenship or anything. Not even knowing zip of the language matters.

Knock on effects is that certain security sensitive jobs for the US government are also out since they are dual citizens.

And you cannot renounce your S. Korean citizenship until you are 38. (If you know about this you can supposedly renounce before you turn 18.)

Somethiing similar happens to men of Turkish descent born in Germany. Even if they have the German nationality, which is possible after a couple of generations, the Turkish state does not recognize it and they are obliged by Turkish law to do military service in Turkey, which is no piece of cake. There may be real fighting involved: PKK; Syria, Irak… They cannot renounce their Turkish nationality either. The only way out is never to set foof on Turkey. Ever.
Turkey being the country that coined the term baksheesh there are rumors that you can buy your way out. IDK about that. Maybe.
And my information is from about ten years ago, the situation may have changed. I doubt it, though.
In any case Turkey is an example of what it means NOT to recognize dual citizenship, just like your South Korean example seems to be too.

I know someone who— I hope I have all of this straight— was born in the U.S.A. but at some point moved to Israel and went to school there. He also had Israeli citizenship because both his parents were Israeli. He was subsequently drafted into not-optional military service for a few years (fortunately he was resourceful enough to avoid a combat role). He was not an officer or anything, though, so apparently the US did not care too much and he remained a U.S. citizen, which sure came in handy when it was time to move back to the U.S.

Shamima Begum, (born in London) who went to Syria along with some other teenage girls to join up with IS, has had her UK citizenship revoked for doing so. In theory she is entitled to Bangladesh nationality by descent (though she never lived there) so technically it does not leave her stateless. Statelessness was something the old Soviet Union did to dissidents, and action which the West condemned, at the time.

Chistabel Bielenberg had to renounce her British citizenship to marry her German husband in 1934, as German law did not allow dual nationality (at that time, its more complicated now). She had to hand in her British passport to the German consul in London before he handed her a German one.
After the war, having been peripherally involved in the 20th July Plot, they left Germany for Ireland and she renaturalised as a British citizen.

In recent years, it has become quite common in Britain, for those who can meet the criteria, to claim Irish citizenship and the passport that goes with it, as it allows them to continue to travel to EU states without restrictions. In most instances they have no other connection with Ireland and no wish to live there.

I think the Shamina Bergun case is an interesting one concerning the revoking of citizenship rights, and quite illustrating.
To state the obvious: she was a foolish young woman and she deserved to be punished for joining ISIS. But was revoking her citizenship the right punishment? I think it was not. Let me elaborate.
Compare her situation with what happened to me concerning my dual German/Spanish citizenship. Both Germany and Spain did not recognize the other nationality, so if those countries would have been unhappy about me holding the other nationality they would have had a couple of options to solve this mini-crisis, but revoking their own citizenship, that is, the Germans depriving me of the German statehood or the Spanish depriving me of the Spanish nationality would have been a no-go. Because, as they did not recognize the other nationality as valid, that would have rendered me stateless formally within their legal logic. And that is something civilized states don’t do, or at least are not supposed to do. They would have had to find ways to pressure me to give up the other citizenship “voluntarily”, claiming, within their logic, that it is unvalid anyway. Depriving me of their respective citizenship would have made them implicitly recognize the other nationality as valid, which is just what they did not accept. So the solution to this day is to simply ignore the other nationality, although I never made a secret of it. Fortunately for me, it is not a big deal for either state.
Depriving Shamina Begum of her nationality on the grounds that she could claim another statehood by descent is in my eyes a spurious argument. It was a legal sleigh of hand, particularly considering her biography. She always lived in the UK, never in Bangladesh. And that rendered her stateless, at least temporarily.
Sentencing her to a prison sentence and/or a fine would be fine IMO, but depriving her of her british citizenship was spiteful and diminished the UK’s moral standing. This was unnecessary and petty.
I have no doubt that both Germany and Spain could have stripped me of my nationalities if they really wanted to, perhaps if I had been a terrorist or a serious criminal (which I was not) they would have done so. I am under no illusion in this regard: I remember how both countries have treated terrorists in the past (see the GAL in Spain and the German Autumn 1977). But those are the actions that diminish the legitimacy of states, they don’t enhance it. And stripping Shamina Begum of her right to British citizenship did not enhance the legitimacy of the United Kingdom either. Not in my opinion, whatever it is worth.

My Swedish passport shows Place of Birth as “Utah, USA”. That field is right next to my photo, and I have no doubt that customs agents regularly check birthplace when you present yourself to them. So yeah, they’d easily know that I am either dual or that I renounced at some point (which would probably need proof should I ever do that)… plus I’d have needed to apply for ESTA and pay the fee before traveling there anyway.

However, I do use my Swedish passport to fly out of the US. The reason: otherwise the ticket agent gets all concerned about my not having a return ticket bringing me back to the US. I simply give them my other passport and they don’t have to worry about it.

Technically you’re not supposed to do this; you’re supposed to leave a country on the same passport that you used to enter it with. I haven’t had any trouble to this point, and given the direction the US is moving currently I don’t plan to return there again to see if this has changed (for the worse, no doubt!).

So, I’m a basic White Bread Midwest American, but of Swiss ancestry. When I turned 18, we were in Switzerland and the relatives took me down to the Canton head office. The goblin in charge (I am NOT kidding, it was just like Gringott’s in Harry Potter) took a vintage fountain pen and hand-wrote my name into a huge yellowed ledger.

They then announced that I could buy and sell property in Switzerland. And that, should I have a son, he too could be “in the book”. Which he now is.

I’ve always wondered if we could have dual citizenship. Anyone here know?

(The kid asked me what good that would do and I said “Well, the passport’s a big plus.”)

@Czarcasm I understand you’re being glib, but this board is about fighting ignorance. And your statement is factually incorrect.

A US consular official in Shanghai once 'splained to me that the US tolerates dual citizenship. At times it’s no big deal, and the pendulum swings and they make it as unpleasant as possible to keep dual citizenship.

My case. In China, one has to go through passport control to leave the country, and the passport has to have a valid visa (or be issued by the country) that you are visiting. In the case of the US, catch22. US citizens have a passport, and therefore ineligible to get a US visa in a dual citizenship passport. My first kid was born in China to a Chinese citizen (Mom) and a US citizen by birth (me). To keep the Chinese passport, we had to get a “pro-forma” (aka fake) visa from the US consulate. It looked like a real visa, but only for the purpose of leaving China, and not valid for entry to the US. The consulate got less accommodating of the annual pro forma visa, and then kinda nasty (we had to apply for the visa interview on the regular website for non-citizens, long wait list, were made to come in at 8:00am and were literally the last case with no one else at about 12:30 to be interviewed). The next year my twins were born, and knew we couldn’t keep doing this. I told the consulate I was giving up the Chinese passports when we landed in LA, and they grudgingly agreed to “one last pro forma visa.” The work around would have been to use the Chinese passports, get Canadian visa’s, fly to Canada and enter with the Chinese passport, leave Canada with a US passport to visit the US, then back to Canada on the US passport, then and only then fly back to China on the Chinese passport.

And yes, we landed in LAX, drove straight to the Chinese embassy, and watched as the clerk voided the Chinese passports and stamped big holes in them. End of dual citizenship.

I am not being glib, and I think you misunderstand what I am saying-I am talking about China’s take on the subject, not the U.S.'s.

I had dual US/UK citizenship for many years before finally renouncing the US one several years ago. I would fly into and out of the US with that passport then use the UK one at passport control in London. The birthplace listed on my UK passport just says “Memphis”, no mention of state or country. I haven’t yet travelled to the US with just the UK passport so don’t know if I’ll get any hassle or not.