Suddenly out of the skies, they descend in swarms. Silently, they keep watch and gather intelligence, or swoop down with a screeching whine for a final, explosive strike. Drones, or UAVs (unmanned aerial vehicles), are defining modern warfare, posing a challenge that most militaries are still struggling to counter.
With the realisation that cheap drones can overcome military asymmetry and economic limitations, they have quickly become the central tool of war, particularly where adversaries differ in capabilities. If the use of gunpowder rendered fortifications redundant, and the advent of battle tanks made cavalry obsolete, today it is the ubiquitous, inexpensive drone that is beginning to supplant fighter aircraft and costly cruise missiles.
“We are at an inflection point in warfare that is as disruptive as the tank replacing the horse, with the major difference being that this time round the cost matrix has drastically reversed,” said Sai Pattabiram, managing director of Zuppa Geo Navigation Technologies. “Defence equipment once considered gold standard has rapidly turned into liabilities capable of bleeding a nation financially.” He said this was rapidly dominated by constant innovation at the electronic layer, with automation and AI emerging as key growth areas.
Firefighters work on an apartment building hit by a Russian drone in Kharkiv, Ukraine | Reuters
Drones are now everywhere. Their omnipresence, silent surveillance and lethality create a pervasive fear and sustained psychological pressure—amplified by the uncertainty of when, where and how they will strike—while imposing a heavy economic burden on adversaries and stretching air defence systems thin. If military discourse once centred on fighters, submarines and missiles, it is now increasingly about drones or UAVs. After all, a small one-way ‘suicide’ drone or loitering munition functions much like a micro cruise missile.
The first war in which drones made a decisive impact was the 44-day Armenia-Azerbaijan conflict in 2020 over the disputed Nagorno-Karabakh region. It is remembered for how Turkish Bayraktar TB2 drones destroyed Armenian T-72 tanks. Many strategists even declared that the era of battle tanks was over, as slow-moving armour became easy targets for drones.
The second conflict is the Russia-Ukraine war where both sides have employed drones for intelligence, surveillance, reconnaissance and combat on an unprecedented scale. One of Ukraine’s most striking drone operations took place on June 1, 2025, when a large number of long-range, first-person-view (FPV) drones targeted multiple Russian airbases deep inside Russian territory.
Russia, however, adapted quickly. It deepened cooperation with Iran and established domestic production lines for variants of the Iranian Shahed-136 drones, redesignated as Geran-2. These drones, with a reported range of up to 2,500km and warheads of 50–100kg, have been used extensively against Ukrainian targets.
There is also a stark economic dimension. Ukraine has often had to deploy air defence missiles costing several million dollars each to intercept far cheaper drones. This imbalance forced Kyiv to develop lower-cost interceptor drones. While a Geran-2 may cost around $35,000, Ukrainian interceptor drones can cost as little as $3,000–$5,000, turning the contest into a race for affordability. “Ukrainian interceptor drones have already begun reversing the cost economics away from the ‘Shahed’, forcing the Russians to move towards lower-cost alternatives,” said Pattabiram.
The third conflict in which drones played a critical role was the war triggered after Hamas’s October 7, 2023 attacks on Israel. Israeli systems such as loitering munitions and small ISR (intelligence, surveillance and reconnaissance) drones acted as significant force multipliers in the ensuing operations.
However, the most striking impact of drones is arguably being seen in the latest conflict in the Middle East involving Iran, Israel and the US. With parts of its conventional military capability degraded, Iran has increasingly relied on asymmetric tactics, deploying swarms of drones against US military bases, infrastructure and commercial targets across the Gulf region. “Iran’s investment in indigenous drone technology has been a critical enabler,” said Group Captain (Dr) R.K. Narang (retd), a former Indian Air Force pilot and senior fellow at the Manohar Parrikar Institute for Defence Studies and Analyses. “It pursued self-reliance far more seriously than many others in the region and did not depend heavily on licensed production.”
The persistent threat of drone attacks in and around the Strait of Hormuz has disrupted maritime traffic, delivering a significant shock to global energy flows and the world economy. Drones also serve a strategic purpose for Iran as they enable sustained, calibrated pressure, aligning with Iran’s broader objective of extending the duration of the war.
Reports from the Iran war indicate significant attrition of aerial assets, including high-value platforms and multiple medium-altitude, long-endurance (MALE) UAVs such as the MQ-9 Reaper. “Turbo-prop MALE UAVs like the MQ-9, Hermes-900, Hermes-450 and Heron have proved vulnerable in high-threat environments, underlining the need for stealthier platforms for future combat operations,” said Narang. At the same time, the use of inexpensive drones allows countries like Iran to conserve their limited stocks of costly missiles. In contrast, the US and its allies have expended large numbers of expensive interceptor systems, along with Israel’s multi-layered air defence systems—at far greater cost.
Pattabiram believes the scale of defence manufacturing will soon shift dramatically, from thousands to potentially millions of drones. “Drones will evolve from being equipment to consumables, much like ammunition,” he says. Above all, the inability to fully counter large numbers of inexpensive drones suggests that future wars may be longer and more attritional than previously assumed. Until an effective response emerges, nations will have to prepare for protracted conflicts—challenging the long-held belief that modern wars are short and decisive.