How to manage nuclear armed missiles in a spaceborne combat environment?

Question

Thanks to all the members in my previous question regarding nuclear armed missiles (nukes). From those responses, it turns out nukes are more powerful than I expected they would be in terms of spaceborne combat.

So for the purposes of my worldbuilding (WB) exercise, I am left with a conundrum on how to deal with them.

First some basic relevant background. This is the WB as I've envisaged, but I certainly welcome additional ideas.

1. Setting is millenia in the future;

2. There are no what I see as purely handwavium weapons - no disruptors, no transphasic torpedoes, no turbolasers, no hyper-relativistic kill vehicles (ie kinetic energy (KE) weapons with high partial c velocities);

3. Weapons in use are lasers, coil/railguns, missiles, particle cannons, drones. Although, in my setting, large capital warships are virtually immune to lasers (handwavium (HW) tech), although they are still used as point defences (PD) and to disable/destroy vessels w/o the HW tech;

The problem for me is nukes. Warships in my WB are large (hundreds of meters long) and heavily armored (tens of cm of armor). I further envisage that initial salvos will be volleys of missiles. The problem is, as pointed out to me, a single nuke, detonated close to a vessel, can virtually vaporise it, if not simply shred it. That then means that it is pointless to have large, heavily armored warships if they can be so easily destroyed. Which is not what I want. I want more protracted "slugfests"

So, how to deal with nukes? My solutions so far:

1. Ban them by Galactic Treaty. Such treaties exist in my WB (mass drivers (other than coil/railguns) for example). However, given how effective they are, it doesn't seem like parties would so easily give them up.

2. Make PD extremely effective, but then, why have missiles at all?

3. Special "anti-heat" armor, which is what I'm kinda leaning towards, but I was hoping for something more creative. This option keeps nukes in play, while option 4 below pretty much removes nukes from the table altogether. Note, there are no "Star Trek" shields in my WB. There is also no artificial gravity (via graviton generators et al), so missiles can't be deflected using "graviton beams".

4. My most "creative" solution is what I call "radiating countermeasures". Essentially, they would fry all electronic equipment on a missile/drone at a range of 5-10 km out, thus, a nuke could never detonate close to a warship (at least while the countermeasures are working). In this case, missiles would instead have multiple KE warheads that are ejected from the missile just outside the countermeasure range, which would be terminally unguided, but otherwise unaffected by the countermeasures.

So my question, how do I deal with nukes in the context of my WB exercise? Input is desired. Hopefully I've given enough detail without too many boring WB details. Thanks.

Answer 1

Decline

Your world is not a post scarcity world. Stuff is scarce. The ships your people use are all hundreds of years old. There are not new inventions. Technology has not advanced in a millenium. People are aware that they are not as good as their ancestors were. People get by. It is how it is.

Back in the day a lot of nuclear bombs were made and a lot of nuclear powered stuff. As a result uranium is now hard to find, or so the story goes. Even if people could find it, no-one has refined uranium for a long time. They probably could look up how to do it. They could, but they don't.

People don't use nuclear weapons because they don't have any more nuclear weapons. They use the weapons they have, which are the weapons they inherited from the previous generation, and them from the people before that.

Answer 2

Point defense should be extremely effective in space, especially at close (<25 km) range; there's nothing to hide behind nor any clutter after all. However, your nuclear antiship missiles can still get through with the same mechanics real world nuclear weapons need to reach their target: penetration aids: https://en.wikipedia.org/wiki/Penetration_aid . Each missile salvo launched by your ships is accompanied by an even larger salvo of missile borne decoys, jammers/flares, trick/gimmick missiles like a missile carrying a bomb pumped laser to do damage as the salvo approaches in hopes of helping the rest of the salvo get through, etc. to help the real nuclear antishipi missiles reach their target. This gives you the huge missile slugfest that you want as both side try to saturate each other's defenses, albeit at the cost of mammoth resupply problems.

Answer 3

Trust

Light speed delays would prevent "the government" from providing real time authorisation to use nuclear weapons, so whoever is commanding a nuclear-armed ship must be trusted sufficiently to be given discretion regarding when to deploy a potentially strategic weapon in tactical situations. Given the speed at which engagements could develop, the relevant weapons officer on duty at any moment must be able to make the decision to deploy nukes in an instant without time to get multiple authorised officers to turn keys simultaneously or any of that nonsense. (Before anyone argues that "there is no stealth in space" and there is potentially plenty of time for multiple key turning - what happens if a "friendly" ship or station within a few (hundred) km suddenly reveals their true colours and launches at the warship?)

This means that each ship must have many officers each completely trusted to have sole authority to launch a nuclear weapon without any checks or balances - or one autonomous AI with completely trusted programming. Frankly, a universe where sapient beings can be completely trusted but are still trying to blow each other up in space is a bit hard to believe, so lack of trust is an easy explanation for lack of nukes. (Yes, a spaceship can cause damage in many ways, but against civilian populations that damage is greatly multiplied with access to a magazine full of nukes.)

Maintenance

It's hard to get solid information on this one due to the information being sensibly classified, but there are questions about the shelf life of nuclear weapons of various types. It seems that the United States is probably able to extend the life of its existing nuclear weapons to about 75 years with some unspecified (highly classified) maintenance. More regular routine maintenance is apparently needed more frequently - I don't know how often and your readers probably don't either.

The question does not specify whether the universe has FTL or not, but if ships are potentially operating without resupply for more than a few years then nukes may not be a feasible weapon to carry. For lightspeed-limited ships on interstellar trips, nukes are probably a non-starter unless the warship has the ability to mine, refine and process radioactive materials and manufacture weapons from scratch after arriving in a system.

Nuclear dampers

This is probably too far into the handwavium spectrum rather than hard science, but worth mentioning. One of the high tech level items in the Traveller TTRPG universe is the nuclear damper used for defence against nuclear weapons. To quote from the 1978 version of Book 4 - Mercenary, which first introduced these:

A common term, damper units actually may be used to increase or decrease the stability of atomic nuclei. Projecting from two separate stations, the intersection of the two transmitted broadcasts produces a series of nodes and anti-nodes. In the area of the nodes, the strong nuclear force is enhanced, making the nucleus more stable. In the area of the anti-nodes, the strong nuclear force is depressed, making the nucleus much less stable. Anti-nodes are focused on incoming nuclear warheads, causing them to shed neutrons at low energy levels, rendering the warhead inoperable. The range of the damper field is proportional to the distance separating the two projectors.

Answer 4

Your real problem is heat. (So you need super efficient heat sinks and highly efficient radiators)

All weapons, lasers, rail guns, nucs, particles beams every single one will produce heat on impact. (They also produce heat inside the ship launching them but that is less problematic.)

And in a vacuum heat is very, very hard to get rid of. In this far distant future world you are using huge ships with huge weapons that will generate megawatts of heat. Even a slug launcher generates heat in impact. So don't worry so about the nuclear bombs. Point defenses will stop some, some you can evade/spoof with decoys and countermeasures and some will hit (explode nearby- a relative term in space) leading to you having to 'soak'/take damage (and heat) from the explosion.

The key is having effective means of getting rid of all the heat the ship is absorbing, both from your own weapons and from hits scored by the enemy. Because otherwise your crew will literally cook alive.

Answer 5

There is one good point about warfare in space - you do not have to worry about radioactive hazards making the area uninhabitable for centuries, or clouds of radiation floating into populated areas.

I suspect the best defence against NAMs in space warfare would be other NAMs. For essentially the same reasons NAMs would be very effective against space dreadnaughts, they would also be very effective at taking out NAM missiles (torpedoes) themselves. No shock wave in space, but I am sure the radiation storm would be very effective at frying guided weaponry, and like horseshoes, close counts. They do not have to be very big NAMs, and comparatively speaking, they are really cheap to build. I am sure hundreds of NAMs on a dreadnaught in space would be no problem.