Any RF signal can be jammed (and satellite communications work through RF signals), just transmit garbage data with higher power than the real user.
Yes, any RF signal "Theoretically" can be jammed. Just how hard it is, and how practical it is the matter. If I have unlimited resources and bottomless power, I can jam EVERY RF signal in this world.
But I can tell you as a matter of fact as a Tactical Officer who was trained with Type 4 NATO SATCOM protocol, you can't.
If you know anything about satellite jamming, there are only two ways you can jam a satellite, they are jamming their uplink and downlink com. Again, this might have work if you use commercial satellite, for Military Satellite, you can't, because you need to be able to filter out the encrypted comm burst to connect the uplink module, and that's also depends on the node ends, whether or not they will switch transfer mode. If they do, you will have to do over.
But that wouldn't be an issue because you will need to position your jamming device quite close to the signal interception, which mean if you do that, people will know you are trying to jam a military satellite.
Jamming Downlink is another issue, first you need to know where that connection is coming from, and then intercept said signal, you can't intercept that signal until it bounce back to the node, otherwise you would have no signal to jam, and it would have been protected by encryption anyway.
What you are essentially referring to is a kind of DDOS attack, again, it does not work against military satellite, first, you have to have a stronger signal and computing power to do that, second, you have to be in close proximity of the signal.
In fact it's more easy jamming of sats than terrestrial, because you can do it from a lot of places to the sat. Communications can be directed in a beam, but if you know the position (and all sats positions are known) you can do jamming.
What you failed to see is you can connect to multiple signal with a single node. and 1 will become 2, 2 will become 4, 4 will become 16, while I cannot tell you how much is the maximum node connection, I can only say it is a lot more than 8. and then you have more than 1 node, and you will need to jam ALL THOSE to be able to successfully jam the comm.
And that without talk about the effects of HEMP bombs, that will do useless almost all freqs.
umm.....no. EMP does not affect UHF
The effects of HEMP span a wide frequency range (very low frequency to a few hundred megahertz [MHz]), and encompass critical commercial and military frequency bands. HEMP effects also produce damaging currents within power transmission, distribution, and communications lines resembling effects of geomagnetic disturbances or storms (e.g., solar flares). These disturbances can damage or destroy both electronic control equipment and the power transformers associated with electric grid distribution. Protection from HEMP effects is, therefore, essential.
www.wbdg.org
It may affect some low bandwidth UHF, but over 800Mhz are considered secured from HEMP. And UHF goes up to 3GHz
WWIII wont be televised, it will be silence, and only we'll hear the sound of Russian nukes triggering over our heads.
First of all, any hint of Russia using nuke is stupid. First, it wouldn't change the status of the battlefield for the Russian, it will only draw NATO closer to the conflict. You would have to either drop Megaton level nuke to make a different or hundred of <40Kt device. 1 40kt device have a damage radius of 15-20km, if Russian just nuke the front line, they would have to use hundred, if not thousands of tactical nuke. That's more or less the same as starting a global thermonuclear war.
Second, using nuke would go against the original goal, if Russia don't want part of Ukraine, why invade? Why not just use their air force and bomb Ukraine back to stoneage? Or better yet, why not use nuke on day 1? Nobody like to lose soldier for nothing, if they want to use nuke, they would have use it a long time ago.