The year gone by, 2025, was notable for war. Besides the ongoing Ukraine-Russia conflict, it saw a renewed Israel-Iran war, with the US jumping into the fray. The civil war in Sudan continued to take its terrible toll, and the Cambodia-Thailand fight was a geopolitical surprise. Hapless Gaza was pummelled for the second year in succession. Meanwhile after a breakdown of their ceasefire with the US, the Houthis continued their war against shipping in the Red Sea.Wars are wars, and they always come with death and destruction. The war in Ukraine is a total war involving all domains of conflict, land, sea, air, cyber and space, while those in Israel, Iran, India and Pakistan were short aerial clashes with controlled destruction. Gaza tells us how total wars end, in total destruction, though in this case it is completely one-sided.For decades, modern war was imagined as fast, decisive, and dominated by advanced aircraft, precision strikes by tanks and artillery, and the application of overwhelming force, essentially military-on-military contests. But, these recent wars recent have shifted paradigms.The wars continue to be dominated by technology, but as in Ukraine, they remain lethal, but they can be slower and messier. They are also a warning as to where war will take you if unchecked by ethical concerns or law. None of this has reduced the propensity of nations to use war as an instrument of policy.Drones and unmanned systems:What the war in Ukraine tells us is that small, inexpensive drones – many originally designed for civilian use – have become essential tools of war. They are used in huge numbers and lost just as quickly. This constant aerial presence has stripped the battlefield of secrecy. Troop movements, supply routes, and defensive positions are now routinely spotted within minutes. In modern war, if you can be seen, you can be targeted – and drones have made almost everything visible.Even more transformative has been the rise of first-person-view, or FPV, drones. These small machines, piloted remotely through a live video feed, have turned into precision strike weapons. For a fraction of the cost of a guided missile, an FPV drone can destroy an armoured vehicle, hit troops in trenches, or strike buildings. Instead of a few costly weapons hunting many cheap targets, Ukraine has shown how many cheap weapons can overwhelm and destroy costly ones.Drone warfare in Ukraine is not a one-sided story, in fact after initial setbacks the Russians came back strongly with their own drones and electronic warfare systems .This struggle has driven rapid innovation. A case in point are fibre optic guided drones that trail a wire through which it is guided and cannot be jammed. Drones are modified, improved, and replaced in weeks, not years, as soldiers adapt directly to what works and what fails at the front.In the May India-Pakistan war, too, drones were used but not as extensively. India used one-way drones like Israeli Harops and Harpies to target Pakistani air defence systems. In turn Pakistan used Yiha III loitering munitions and large numbers of the somewhat ineffective Turkish Songar drones to target Indian air bases.Drones are not just about the air. The modern naval landscape is undergoing its most significant shift with the rise of maritime drones. Unmanned Maritime Systems (UMS) can be underwater or surface vessels or aerial surveillance and attack systems. Ukraine, without a navy of its own, has used Unmanned Surface Vessels (USV) operating as drone swarms to neutralise the Russian Black Sea Fleet.Unmanned underwater vessels are currently used for mine-clearing and mine-laying missions. Some of them are as large as small submarines like the Boeing Orca. Since communications with submerged vessels is difficult, the AI revolution could lead to the next generation of autonomously tasked drones. China has its own set of maritime drones, large ones similar to the Orca, and the smaller ones like the HSU100s. The Russians have unveiled their nuclear powered Poseidon system which can be used for nuclear weapon delivery.TanksTanks remain important, but the Ukraine war has shown their vulnerabilities in the absence of integrated support. Anti-tank guided weapons and cheap drones have eroded some of their decisive battlefield utility. This suggests doctrine – rather than tanks themselves – may be overdue for revision.Defensive warfare and information dominanceAnother striking feature of contemporary war is the return of defensive warfare. In Ukraine, trenches, minefields, and fortified positions – often associated with World War I – are once again common. Anti-tank weapons and air defences have made rapid advances extremely costly. The Israel-Iran war and the India-Pakistan one have brought out the importance of air defence, particularly against drone swarms and ballistic missiles. Israel, for example had complete control of the air, yet it suffered significant damage from Iranian missiles in the June war, like the hypersonic Fattah 2 and the Khaibar Shekan, which used a manoeuvrable re-entry vehicle to avoid interceptors.Equally important is the role of information. This was evident in the short India-Pakistan war. Information warfare – through disinformation, cyberattacks, AI-powered deepfakes – became as important as physical combat. Winning international support depended not only on military success but on controlling the narrative. India won the war, but Pakistan convinced itself and many others that they bested us. The world knows better now, but first impressions are often the last ones.Logistics sustainment and private sector rolesThe conflicts have also challenged the idea that modern weapons alone guarantee quick victories. Precision missiles and advanced systems matter, but they have not eliminated the importance of manpower, logistics, and endurance. In Ukraine supply lines, ammunition stockpiles, and industrial capacity have proven decisive. Armies cannot fight without fuel, shells, and spare parts, no matter how advanced their technology is. This has brought attention back to an old truth: wars are ultimately contests of production and sustainability where it is clear Russia’s size and its willingness to take casualties is making the difference, albeit very slowly.In both the Israel-Iran and the India-Pakistan clash, it is evident that all the parties saw a significant depletion of their ammunition stocks, especially to deal with adversary missiles and drones. Israel has not given the figures, but US officials say that by the end of the war Israel was running low on anti-ballistic missiles. Likewise, it is believed that India and Pakistan, too, ceased fire because they were running short of interceptor missiles.The Ukraine war has seen a massive integration of civilian companies like Space X (Starlink) providing critical means of communication to Ukraine, as well as firms like Maxar, Planet Labs and BlackSky providing commercial imagery, Palantir helping to integrate satellite data for target acquisition. Ukrainian companies are using 3D printers for drone parts and have developed technology for transforming commercial drones into military weapons. Importantly what the Ukrainian experience has revealed is that the cycle of innovation and obsolescence moves fast when it comes to drones. The key driver here is electronic warfare which make technologies that were once effective quickly vulnerable.AI and the future battlefieldAI has already made an appearance on the battlefield. But this is just the beginning. On October 6, Lt Gen Rajiv Sahni the director-general of the Indian Army’s EME Corps revealed that AI was “extensively used for multi-sensor and multi-source data fusion in real time” in Operation Sindoor. He said that with the help of AI, the army was able to identify, prioritize, locate and engage targets with a success rate of almost 94%.AI is likely to reshape warfare across decision-making, autonomy, and information dominance over the next five years, with emphasis on faster decision cycles, more capable autonomous systems, and more integrated cyber and space operations.ConclusionAll these are lessons that come from events in 2025. In the meantime countries continue to invest in even more deadly ways of making war – 6th generation fighters, autonomous drones, hypersonic missiles, lasers, electromagnetic railguns, fire and forget unmanned submarines and so on. As is well known, sharply rising defence expenditures are a feature of the Trump era.These developments suggest future conflicts will be increasingly multi-domain, information-centric, technologically democratised, and of course, lethal and destructive. Weapons of war evolve continuously, but instruments of peace must be deliberately built. 2025 has seen how many of these have been gutted as civilians and civilian facilities have been deliberately struck and war has involved disproportionate use of force. If the focus of the world is only on winning wars, not in preventing them, the road ahead could be a rocky one. The United Nations has proved to be next to useless as a guardian of peace, especially since its permanent members, charged with promoting global security are, more often then not, themselves involved in wars.Manoj Joshi is a distinguished fellow at the Observer Research Foundation in Delhi.This piece was first published on The India Cable – a premium newsletter from The Wire – and has been updated and republished here. To subscribe to The India Cable, click here.