This is mostly an advertisement for the Leopard II, but it is no less generally relevant:
Vladimir Putin's annexation of Crimea and massing of troops on the Ukraine border has left frontline nations pondering the strength of armored brigades that have shrunk since the collapse of the Soviet Union, Haun said in an interview at KMW's Munich base. ...
Demand for Cold War hulks like the Leopard 2, which fires shells that can penetrate 56 centimeters (22 inches) of steel from 2 kilometers (1.3 miles), faded in Europe as relations with Russia improved, with the focus of tank deployment shifting from the north German plain to the deserts of the Middle East.
Long ago, I argued (in a piece that was never published) that the 1991 Persian Gulf War proved that heavy armor is still useful and not irrelevant. I did get a piece published that pushed back on the idea that the ultra-light Future Combat Systems could replace the Abrams (See "Equipping the Objective Force"). The Iraq War in both the major combat and insurgency portions proved the value of heavy armor.
Even the Canadians who abandoned heavy armor decided that their Afghanistan campaign required heavy armor.
Yet still I had to remind readers in posts from time to time that heavy armor is still necessary.
Now the image of so many Russian tanks massed across the border from Ukraine in the spring has reminded Europeans about the value of heavy armor.
I will say that the fact that heavy armor is still useful does not mean they are invulnerable to enemies. Our Abrams were darned near immune to the enemy there--who lacked air and fire support--as long as they kept their frontal aspect facing the enemy, but tanks can be destroyed.
Top-attack munitions that target the weak spot of heavy tanks, precision artillery, rockets, and air power will inflict casualties on tanks that could shock those now remembering the value of heavy armor.
Don't forget that in World War II, tank battles would often leave even the winning side mostly without tanks destroyed, damaged, or broken down. But if you owned the battlefield after the fighting, you repaired the damaged or broken down tanks, shipped in replacements for the destroyed tanks, and the mostly surviving crews got back to work.
I suspect that we will need to get with the program and put active defense systems on our tanks (to supplement and not replace heavy passive armor) to shoot down incoming rounds. The Russians, I believe, pioneered this. The Israelis have made it work and that may have kept their vehicle casualties down in the recent Gaza fighting despite Hamas investment in anti-tank weapons and tactics.
No weapons system lives forever. But as long as we need mobile protected firepower, heavy armor (and supporting forces--let's not get tank-pure nuts here) is still needed.
UPDATE: Sigh. We want smaller lighter vehicles with more protection without the weight of passive armor. Yeah, and wish for a pony, too, eh? It isn't clear from the article, but the graphic makes it clear that a small unarmored vehicle that defeats rather than deflects incoming rounds is preferred. And this is consistent with the thinking that I addressed in the Military Review article I authored above.
Funny, I actually addressed controlling the battlefield before. And I've discussed the flaws of viewing active protection as an alternative to passive (and heavy) armor rather than as a supplement.
UPDATE: Related on the RMA (Revolution in Military Affairs) that is supposed to make tanks obsolete. Good points, but if we are in an age of small wars I think it is because we haven't had a great power war lately rather than because great power wars are no longer viable. Europe went a century between Napoleon and World War I without a great power general war (well, disturbingly enough there was the multi-great power Crimean War--with an eerie parallel in speed of reporting from the war--in that era and Prussia went to war with Austria and France in that time).
One large-scale war with multiple great powers and nobody will say we are in an era of small wars.