A very interesting question...here are a few things that come to mind:
-Missiles: We are in the process of seeing a major change in the threat environment that is being brought on by the continued development of anti-ship ballistic missiles (ASBMs) and hyper-sonic weapons. ASBMs are here today, and hypersonics are (potentially) right around the corner, depending on how much of the Russian propaganda surrounding the ZIRCON you choose to buy in to. Both of these weapons are going to be even more difficult to counter than the sea-skimming subsonic and supersonic threats that are common today, and which the current generation of air defense systems (including AEGIS) are designed to counter.
https://nationalinterest.org/blog/buzz/russia-has-made-some-dangerous-changes-its-zircon-hypersonic-missile-81426-Energy Weapons: Lasers are already starting to go to sea, mostly as "soft kill" devices intended to blind missiles and the human operators of air and surface craft alike. Lots of R&D being put into these, though, so there will be more to come. It is possible that we may one day have a "Laser CIWS" that can do hard-kills on incoming weapons.
https://news.usni.org/2019/05/30/navy-to-field-high-energy-laser-weapon-laser-dazzler-on-ships-this-year-as-development-continues-Offensive actions to/from space: Being able to target those long-range ASBMs and hypersonic weapons basically requires a functioning satellite network to provide targeting. If we ever have a major war again, expect satellites will become fair game for destruction. We already have weapons at sea capable of engaging satellites in low-earth orbit:
https://en.wikipedia.org/wiki/Operation_Burnt_Frost-Unmanned Vessels: We talk a lot about "drones," and are usually thinking of the flying kind. However, there is a lot of work being put into unmanned surface craft, some of which are intended to be long-endurance and used for missions such as ASW. This will bring in a whole bunch of new considerations, not the least of which is ROE; if I attack and sink another country's unmanned ASW ship, is that the same as destroying a manned craft? What if I claim that the unmanned craft went rogue and was being a hazard to navigation (regardless of wheter or not it actually was or not)?
https://news.usni.org/2019/10/31/navy-marines-moving-ahead-with-unmanned-vessel-programsOverall though, we also have to recognize that the ships making up the major fleets of the world (US, China, Russia, UK, France, etc) are going to look very similar to what they look like today for at least the next 30 years, and probably more like the next 50. New ships being completed today have at least a 30 year life expectancy, with some, like the FORD class CVNs, designed for 50. So, in 30 years, there will still be a lot of "legacy" ships around, probably with lots of upgrades (like the laser CIWS I mentioned above), but still comparatively less altered than the battleships that were retained after WWI were when they entered WWII.
Been watching this for a while:
http://www.ardentseas.com/
Thanks for this link! I am going to be watching this one now too
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