The Russian invasion of Ukraine has brought guided missiles to the fore, to a very great cost of Russian tanks, armored vehicles, trucks and basically anything that moves. Anti-tank guided missiles have proven to be perfectly capable of turning kinda-modern armor into scrap metal. Swatting aircraft is a somewhat more difficult task, but it’s being done. The video below seems to show a Ukrainian-made “Stugna-P” anti-tank missile (a manually-controlled laser guided missile that can be set on a tripod and fired remotely) promptly deleting a Kamov KA-52 “Alligator” attack helicopter. The Stugna-P would seem a *terrible* missile for going after a moving aircraft, but this one was hovering… and I don’t care how armored your chopper is, if it gets hit with a missile meant to take out a modern main battle tank, your chopper will do like what this one did, and immediately fall from the sky as flaming wreckage.
For as long as there have been projectile weapons there has been armor. And since then there has been a constant competition between the two for supremacy. And right now, it’s pretty clear that arms (in this case ATGMs) have the advantage over armor. We don’t know how well a truly modern MBT such as the Abrams would hold up against missiles like these, but it’s safe to assume the answer would be “not well.” The traditional response of adding even more armor to the tank is likely not tenable; the M-1 is already so massive that merely transporting it is a problem. So the future of defending vehicles will have to be active: not just the reactive armor that Russian tanks are covered with and that doesn’t seem to be doing them much good, but point defense systems that use guns, lasers, missiles, jets of explosively generated molten metal, blast waves, hell, maybe even force fields. None of these will be “cheap.” This will put effectively-armored vehicles outside the reach of many militaries in the face of relatively inexpensive missiles. Perhaps for a time war will simply be cost ineffective. Won’t that be a hell of a thing.