Among the 'cutting edge' technologies being developed or experimented with now are:
Nano-Technology - to effectively 'grow' products instead of fabricating them.
Genetic Engineering - of both plants and animals as well as bacteria
Artificial Intelligence - including autonomous military and civilian machinery/weapons
Micro-Swarm Drones - microscopic or near-microscopic machines deployed as swarms to accomplish attacks or surveillance: think manufactured beehive that can be given orders.
Fusion Power - which may soon be Present Tech instead of Future Tech
Neuro-Implants - 'Cyborgizing' people with computer interfaces and other electronics implanted directly into them
'Way back in the 1970s a great deal of work was done on conceptualizing Satellite-Mounted Weapons, all of which development was brought to a halt by treaties 'de-militarizing space'. These included high-density metallic rods that could be dropped at super-hypersonic speeds (30 - 80,000 kilometers per hour) to smash targets as small as individual vehicles, satellite-to-ground guided/cruise/hypersonic missiles, Anti-Satellite weapons (notably, Project Burro, or the Anti-Satellite Satellite - read the initials). Also, as far back as the 1970s it was discovered that Satellite surveillance could not only reveal the entire map, but also man-made objects as small as individual (compact) automobiles, even through clouds and at night - and that technology has only gotten better every decade since.
1. And with this. Diplomacy should include tech deterrences as a challenge to Science Victory.
2. America ALMOST have a weapon dubbed 'Space Warships'. some even calld it 'Space Battleship'. (And it is not a reconstruction of superdreadnought wreck with an extraterrestal FTL Engine

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To revise my earlier post slightly, I think that settling or establishing colonies on even the easiest Other Planets (moon, Mars, LaGrange sites, asteroids) should be Abstracted: perhaps as a massive Project that allows you to extract new resources from one such destination, but doesn't require you to actually 'play' on another surface/orbital platform, planet or moon. That keeps the game focused on Earth, which is complex enough for most of us, and can save the Interstellar Trip for an end game Victory Condition as the game franchise has done before.
And the Giant Death Robot is not a Futuristic as much as it is a Fantasy unit. All the trends in military technology of the last twenty years are leaning towards smaller, lighter, more mobile, stealthed applications. Making a Dreadnaught on land like the GDR will result in the same fate that befell the dreadnaughts of the Italian fleet in 1940, the US Pacific Fleet in 1941, and the HMS Prince of Wales and INS Yamato: sunk by enemy air power. The early lessons of the Ukraine 'special action' only reinforce this: there are just too many weapons that can take out anything they can find, so watch: for the next decade the major military advances will all be in the area of Not Being Found - stealth for drones, tanks, and infantry as well as ships and aircraft, and even more capabilities to take out enemy heavy weapons like artillery and tanks once identified. The reporters bark about Hypersonic Missiles, but the real Superweapon will be the stealthed Drone, that can search out enemy depots, HQs, tanks and artillery wile remaining immune to enemy weapons, and attack them without warning.
And then again. GDR is heavily inspired by Mech Warrior, in which in the end, also inspired by Super Dimension Fortress Macross. I'm talking about 'American' style mech walkers like this one
And all of these Big Bots as standard military assets begun with Mobile Suit Gundam in 1979. the setting even cited that the 'Mobile Suit' is the Future weaponry that will made BOTH AFVs and Tactical Jets obsolete. In that settings, an antagonist faction named the Principality of Zeon (A nation of human space colonial seccessionists, there's no Aliens in Gundam franchise AT ALL!) was the first to use Mobile Suits to the great effect against every known weapons The Federation (Earth Big Government) have, including space warships of all kind....
And that caused headaches to the Federation. prompted them to reverse engineer thier 'Mobile Suits' which ultemately led to RX-77 'Gundam' to meet the threats, before that the Federation even tried man portable 'Anti-Mobilesuit Missiles'.
F'xis, as well as some Scifi camp, even bet on Bipedal Mechas (GDR and such) as Future Weapons, at some point even ignored Powered Exoskeletal Bodyarmor (Came from Heinlien's Starship Troopers Novel, this too has a big hit in Japan) as insignificant, while IRL premier military R&D did indeed invested in those, both the US Military (For Army and Marines), and Japanese Self Defense Forces (even applied 'Gundam' as a codename, and many associated weapon systems are named after weapons that appeared in the settings, for example 'Suit-controlled UAVs' are called 'Funnels'. Unless there's sufficient CIWS systems for landbased vehicles or small enough to fit there. GDR will have no place here.
To this end the 'Future Tech' adding up to previous generation weapon systems like MBTs should be 'Tech Upgrades' that would represents differences between two 'different generations of the same type of weapons' like 4th and 5th Generation MBTs and Jets. While Jets may have new successor units entirely. MBTs not so much. even Abrams were continious upgrades of what's entered service in 80s. and to this day not even a single 'proposed replacements' repalced Abrams. Same goes to Burkes and Ticoes at sea. I'm not sure if US Navy DDGX will even have a chance to replace the two beyond that any distinctions between 'Missile Destroyers' and 'Missile Cruisers' became irrelevants already.
To the modding perspective.
1. Modern Armor is 'Atomic Era' unit. and a final unit in 'Heavy Cavalry' lineage... if in case of a mod that has 'Light' and 'Heavy' (horse) cavalry converged in Industrial Era as (Line) Cavalry* it will be Second (and last) unit of Tank class
* Civ6 Cav IS indeed Line Cavalry and this unit has a very distict Napoleonic looks while it could... just like Fusiliers, have more flamboyant 'Enligtenment Era Gentlemen' instead.. same capability, different otufits.
in Civ6 Mod o logy, if Modern Armor represents the likes of M60 Patton and T-55 of 50s-60s, what shall be the name of later generations of MBT like Abrams and Challenger of the 80s-90s? since tanks of two different generations have a very different capabilities that in the First Gulf War. American Abrams did take out Iraqi Tanks without the latter has any chance to return fire.
2. And do you think there should be successor to MBT as assault UGVs?
ukdefencejournal.org.uk
And did 'Guided Artillery Shells' joined Russo-Ukraine War of 2022 too? Are these what LAPRAP naval artillery systems developed for Zummwalt tried to do and failed miserably? (LAPRAP objective is to keep Big Guns relevant as artillery particularly in Naval warfare. to be as closely capable as Tomahawl Cruise Missiles but with cheaper shells, it failed).