Maybe the Ukrainians could have tinkered with these warheads and find out how to enable them.... but that is quite risky.
If you have a warhead and a few months (definitely if more then a year) then you have a warhead.
Ukraine has rocketry expertise and nuclear scientists and powerplants. As a nation they were easily capable of reactivating Russian warheads - physical access is total access.
It's an open question among people who research these things whether the weapons stored in Ukraine even had the PALs you're referring to (Permissive Action Link). The literature is contradictory and while wikipedia insists they did, other (quite credible IMO) accounts indicate the PALs were only used on submarine devices at the time. In any rate, it is well known that the Ukranians could have reverse engineered and bypassed the devices; even the US State Dept contemporaneously estimated the PAL would last only "months".
I have no idea what was actually on those weapons but the popular notion that they had the PALs installed is not actually that well founded once you look at the primary sources. Whether it makes any difference is of course another story (I suspect not).
[0] https://russianforces.org/RussianStrategicNuclearForcesC2Pag... page 61-62 see references to authorization codes required for launch in retaliation . See page 64 for launching retaliatory strike when supreme command has been eliminated- again authorization codes are required.
[1] https://www.airandspaceforces.com/article/0297russians/ References the January 25 1995 incident when Boris Yeltsin activated the Kazbek command and authorization system as a result of a false alarm. Again: authorization from supreme command is required
[2] https://thebulletin.org/premium/2025-05/russian-nuclear-weap... section Russia’s nuclear strategy and its war in Ukraine again mentions authorization codes are required for nuclear strike
Reed, Thomas C. At the Abyss: An Insider's History of the Cold War. Presidio Press/Ballantine Books, 2004
relevant quote (from 1992):
> The Soviets were well aware of nuclear weapon safety issues. Even though that subject touches on the internals of weapon design, they were willing to talk and seek advice. They discussed the merits of their transportation containers, which they felt to be superior to U.S. models, and they confirmed that their weapons were “disabled” when in storage, whatever that meant. On the other hand, security (preventing theft or misuse) was a new subject to them. Throughout the Soviet system nuclear weapons had been secured by operational means: people watching people who watched still other people. The Soviets confirmed that there were no electronic or mechanical locking devices on their weapons (as there are in the U.S.), a subject that grew to be of enormous concern as the KGB disappeared, the army disintegrated, and well-financed terrorists infiltrated the country.
RAND corp - From Testing to Deploying Nuclear Forces The Hard Choices Facing India and Pakistan (1998) - https://www.rand.org/pubs/issue_papers/IP192.html
> There are two ways to do this. One way is to use a mechanical device, which prevents the arming of the weapon unless the proper code is entered. In the United States, such devices, used extensively on U.S. weapons, are called Permissive Action Links (PALs). The other way is to use specially selected personnel in an organization separate from the military to maintain weapons control. This method was used in the old Soviet Union and is still used by Russia. India must decide on the combination of these two methods that it wants to use.
Interesting report from Sweden's defense research agency in 2005 - concluding that no-one knows if Russia's tactical nukes have PALs (majority of warheads in UA were tactical) - https://www.foi.se/rest-api/report/FOI-R--1588--SE
I hope this at least shows that it's not quite as settled a question as some make out! And I realize these aren't quite as "primary" as I had remembered; I thought they had more direct quotes, but I do find these sources quite credible.
did they try 0000? https://arstechnica.com/tech-policy/2013/12/launch-code-for-...
If they had nuclear weapons they’d be respected, like North Korea now. No one going to mess with them.
Not really. What do you expect to happen, exactly? Do you think they're designed to detonate if some tamper sensor is triggered, like in a movie?