After a year of fighting in Ukraine, the brutal logic behind Russia's 'human wave' attacks is becoming clear

• Earlier failures and high losses in Ukraine have led Russia to revert to four types of infantry.
• Among them is "disposable" infantry, who are given little training and the most dangerous missions.

The life expectancy of a Russian infantryman may depend on a simple question: What kind of infantry is he? Those used as cannon fodder are probably not long for this world, but those assigned to more valued formations may get the training and equipment needed to stay alive.

After the February 2022 invasion, Russian commanders watched their battalion tactical groups — supposedly integrated formations of tanks, artillery, and infantry — flounder due to poor tactics that made Western-style combined-arms warfare infeasible.

So Russia's military reverted to an informal system from the Red Army's playbook: create multiple classes of riflemen, ranging from the most valuable to the most expendable. It now uses four types of infantry — specialized, assault, line, and disposable — according to a recent report by the Royal United Services Institute, a British think tank.

Specialized infantry may be drawn from regular Russian forces, Spetsnaz special-operations units, or from Wagner Group's professional fighters and generally get training and equipment specific to the role they're assigned, which might be as snipers or heavy-weapons teams.

Assault infantry generally includes elite units such as VDV paratroopers and naval infantry, as well as some Wagner Group mercenaries. They receive extra training and are considered a "skilled and valuable asset," according to the RUSI report. As such, they "are spared some of the mundanity and backbreaking labor of digging in for defensive operations in order to prevent fatigue and attrition, and to allow them to conduct rehearsals for offensive operations."

The grunt work is typically done by line infantry, which is usually drawn from mechanized infantry units and doesn't have the training that assault troops receive. They tend to be used for digging and occupying defensive formations and to support more valuable formations.

At the bottom of the hierarchy is what RUSI terms "disposable infantry." These include conscripts from the Luhansk and Donetsk People's Republics, Wagner Group's prison recruits, and civilians scooped up in Russia's limited mobilization dragnet. They have little training and are equipped only with small arms. They're sometimes sent into battle while high on drugs, according to Ukrainian reports.

Russian practice is now to combine these infantry forces depending on tactical needs. Not surprisingly, the disposables lead the assaults — not in waves but rather in teams of two to five men sent forward to make contact with Ukrainian positions.

"Disposable" infantry troops often continue trying to advance even after being wounded and fight until killed; in some cases they have been fired on from their own lines when they try to retreat, according to Ukrainian accounts. Captured Russian fighters have reported executions under similar circumstances. More cannon fodder will then be sent in until the Ukrainians have revealed their positions and exhausted their ammunition.

According to the RUSI report, the term "human wave attacks" has been misleadingly applied to the way Russia has employed these infantry forces. While successive attacks by small teams are not conducive to battlefield gains, "the continuous conduct of this activity, across all axes, is a form of reconnaissance" allowing Russian forces to find weak points in Ukraine's defenses or reveal strong points to be bombarded, the report says.

Weak points are prioritized for a prepared assault, and stronger positions are designated for attrition by sustained fire from specialized infantry. Disposable infantry is tasked with going forward to prepare jumping-off points for those assaults or to dig positions from which snipers and heavy-weapons teams can fire on Ukrainian forces.

The assault troops attack in larger company-size formations, backed by tanks and artillery as they attempt to outflank Ukrainian defenses. Once their mission is complete, assault forces are replaced by line and disposable infantry, who begin preparing for the next attack.

This rinse-and-repeat approach would have looked familiar on the Eastern Front 80 years ago.

During World War II, Soviet penal battalions were sent on suicide missions to clear German minefields. Then came assault units — Guards rifle divisions, artillery and rocket brigades, or heavy tank regiments — which were massed to achieve a breakthrough and then withdrawn to regroup for the next offensive.

The result was as grim then as it is now. Disposable troops are fed into the meat-grinder and killed or wounded before they can gain enough experience to survive.

Because specialized infantry is used carefully, "the Russians are able to preserve these soldiers thereby steadily increasing the skill of these operators," and assault infantry is "often only committed under the most favorable circumstances, meaning they can achieve their objectives and be rotated out with limited losses," the RUSI report says.

An army that can afford such a cynical use of troops either has enough manpower to waste — which demographically challenged Russia does not — or is desperate because its forces have proven too ineffective for anything else.

Michael Peck is a defense writer whose work has appeared in Forbes, Defense News, Foreign Policy magazine, and other publications. He holds a master's in political science. Follow him on Twitter and LinkedIn.