Your American citizenship is effectively conditional if you want to fly back to the United States. You are now only a citizen if you test negative for Covid or can prove a recent recovery. From the State Department's website:

Effective December 6, the  Centers for Disease Control and Prevention (CDC) will require all air passengers two years of age and over entering the United States (including U.S. citizens and Legal Permanent Residents) to present a negative COVID-19 test result a negative [sic] taken no more than 1 day before departure​, or proof of recovery from the virus within the last 90 days. Airlines must confirm the negative test result or proof of recent recovery for all passengers prior to boarding. ​Airlines must deny boarding of passengers who do not provide documentation of a negative test or recovery.

So, in a medically technocratic move, the CDC turns airlines into its henchmen who will deny access to anyone who tests positive, even citizens.

Everyone is presumed sick and exiled until proven healthy. The burden of proof is on the exiled.

Things would be different if this were a rule made by an individual airline, such as not allowing you to bring a gun on a plane. Since the airline owns the plane, it can morally make whatever rule it likes. The property owner gets to make the rules concerning his property, and there are many such rules for air travel. The CDC, on the other hand, does not own the planes, of course, and I'm more than interested to know what jurisdiction the CDC could possibly have over regulating air travel. The quote above says the CDC "require[s]" – but who are they to require anything?

Germany has a similar rule. Even as a citizen, you can't fly back home to Germany without a negative Covid test result, proof of recovery, or proof of vaccination. Your German citizenship is effectively conditional and tied to your health or vaccination status. Worse, and because German authorities are busy turning Germany into Nazi-Germany again, if you're flying in from what 'they' deem a high-risk region, you a 'required' (there's that word again) to register on a separate, government-run website. For what purpose?

The competent authority [lol, "competent", "authority"] must be able to verify test results or proof of quarantine, vaccination or recovery as well as any exemptions from entry regulations. Your travel and contact details will therefore be collected and passed on.

As they say themselves as you click through the questionnaire, "[c]lassification as a risk area may change at very short notice", so it's really up to their whim how much red tape you are subjected to. What's particularly insidious is that they collect the address where you'll be staying so that, if you're 'required' to quarantine, they can spy on you, 'verify' that you are indeed quarantining, and punish you if you are not. I believe said classification is performed by the Robert-Koch-Insitut, basically the German CDC, which gives the whole thing a similarly medically technocratic flavor and again calls into question on what grounds a medical 'authority' should be able to dictate your travel plans, let alone imprison you upon arrival.

I remember reading that Germany will refund quarantine-related costs such as lodging and foregone work hours. But surely the money you'd receive is from taxes, meaning it's blood money, so you can't accept it.

Australia used to take the cake when it comes to making citizenship conditional. As far as I recall, they used to 'require' that citizens quarantine in specially designated hotels at their own expense, meaning Australian citizenship was effectively tied to wealth. They since seem to have gotten rid of this disturbing regulation, but I didn't check their website in detail (you can only read so much regulatory legalese before it makes you puke).

As far as I know, if you're a citizen of any country, you can be the worst kind of criminal and they'll still let you in. To be sure, they'll arrest and prosecute you, but they'll still let you in. I'm not saying criminals should have their citizenship revoked or made conditional – criminals should have rights, too – I'm instead pointing out that if even crime does not prevent you from entering your home country, your health definitely shouldn't. Also, you're presumed innocent of a crime until proven guilty and the burden of proof lies with the prosecutor, whereas with Covid, as I've said, you're presumed sick until proven healthy and the burden of proof lies with you.

Consider the cost of testing positive as a traveler. It can completely ruin your plans. Since the test result must be very recent (one to two days old depending on the country), you don't have enough time to adjust. You'll also need additional lodging until you test negative, and you'll have to book a new flight on short notice. All this can quickly add up to thousands of dollars. It's less obvious than in the Australian case, but it means that, for the United States and Germany, citizenship is also tied to wealth, and the privilege of traveling abroad by plane even more so than it usually is. Not to mention the emotional cost of being denied access to one's home country, or the psychological cost of being stuck in an unsafe environment. Imagine the cost and misfortune of getting a false positive.

You may object that this only affects those traveling by air, but this is a matter of principle. And it still affects tons of people. Also keep in mind that, like much of the increased TSA nonsense from after 9/11 that never went away, conditional citizenship may not ever go away either, unless we make a huge ruckus and petition a change. Lastly, government regulation tends to grow – now that citizenship is effectively tied to not having Covid, it may soon be tied to more health requirements, and then to additional conditions.

All of this is unnecessary as those who wish to avoid travel and other exposure for fear of catching Covid have always been free to do so.

Exile used to be an extremely cruel punishment for crimes, even an alternative to the death penalty (e.g. in ancient Rome). There's a reason it wasn't practiced anymore until it snuck back in through Covid regulations. Note that, if I am wrong about that and exile had already been reintroduced through other regulations, that does not make Covid exile okay – my criticism would equally apply to those other regulations.

Imposing involuntary medical exile is evil, and these medical technocracies need to be gotten rid of. Citizenship is supposed to guarantee access to your home. Once such access is only granted conditionally, it isn't really your home anymore.

Update 2022-04-19: Minor edits shortly after publication.