Here's What You Need to Know: Sage PLA strategists will craft tactics to disrupt those information links or disable them altogether. Fragment the enemy network and you can fall on the fragments and eradicate them one by one. Or, better yet, if the PLA can sow paralysis in an enemy system-of-systems for long enough to accomplish its goals, then it may not need to bother trying to annihilate individual units.

So “systems of systems”—not individual warriors or ships, planes, or tanks—go to war? Good to know. That’s what China’s People’s Liberation Army (PLA) thinks, at any rate. China’s 2015 Military Strategy, for example, vows to employ “integrated combat forces” to “prevail in system-vs-system operations featuring information dominance, precision strikes and joint operations.” This is how China’s armed forces intend to put the Maoist “military strategic guideline of active defense”—the “essence” of Communist China’s way of warmaking—into practice. They will fabricate systems-of-systems for particular contingencies and send them off to battle. Once there they will strive to incapacitate or destroy enemy systems-of-systems. Firm up your own weak spots while assailing an opponent’s and you shall go far.

You might call this “joint operations with Chinese characteristics” after the Chinese fashion. Earlier this year RAND analyst Jeffrey Engstrom’s monograph Systems Confrontation and System Destruction Warfare shone a spotlight on this dimension of Chinese strategic and operational thought. Engstrom consulted primary-source debates about systems-of-systems to assemble his report, letting Chinese engineers and strategists speak for themselves.

The observations put forth in Systems Confrontation and System Destruction Warfare are at once banal and enlightening. They’re banal in part because system-of-systems engineering is nothing new. It has been around in the West for decades. It got its start among academic engineers in the late 1970s and found favor in the Pentagon during the “transformation” era that came soon after the turn of the century. Almost precisely a decade ago the Defense Department published a Systems Engineering Guide for Systems of Systems, which investigated the rigors of systems-of-systems engineering and explained how to put the concept into effect.

PLA strategists seem to have taken their cue from the Western concept, right down to making the nomenclature their own. Nor is this out of the ordinary for them. Certain imported ideas and phrases resonate with PLA thinkers—sometimes more than with their framers. For instance, PLA officials still use the American acronym MOOTW, for “military operations other than war,” long after it stopped being a fixture in U.S. discourses about military endeavors.

Engstrom’s treatise is also banal because of course metasystems go to war—and always have. An armed host that sends individual weapon systems or soldiers onto the battlefield without integrating their combat power into a unified whole is a force fated for slaughter. It’s little more than a rabble without mutual support among its components, no matter how formidable each warrior or weapon. Disciplined foes strike down fragmented opponents fragment by fragment, soldier by soldier, and widget by widget. Unifying and directing effort has comprised the art of command since antiquity. Only the slogan “system of systems” is new.

Think about seaborne forces. A naval fleet is a system-of-systems that brings together such freestanding complex systems as aircraft carriers, combat aircraft, picket ships, and logistics vessels. The fleet commander oversees the system-of-systems, integrating unlike constituent parts into a whole whose martial strength—if all goes well—is greater than the sum of its parts. Throw in remote sensors and land-based assets that support the fleet, and you have a genuinely intricate system-of-systems. (See below for one such metasystem, from page thirty-nine of the DOD Systems Engineering Guide.) The same could be said of fleets, air forces, and armies since the dawn of the industrial age if not before.

Jeffrey Engstrom renders good service by spotlighting system-of-systems thinking in China. Just because a concept isn’t a shiny new bauble doesn’t mean it has lost value. Novelty is overrated. A vintage concept may not be banal; it may be proven or at least accepted as such. In fact, an idea with staying power across years and decades—active defense, system-of-systems—is worth studying even more than the latest idea. The former may be engraved on a prospective antagonist’s way of marital affairs. The latter could be flotsam, destined to be washed away when the next fad comes along.

Exploring system-of-systems thinking thus furnishes clues into time-tested PLA methods for waging war. And it demands that American and allied forces gaze in the mirror, undertaking some introspection about the robustness and resilience of their own systems-of-systems and their capacity to dismantle and defeat metasystems brought against them. So rather than duplicate Engstrom’s research, let’s review some of the older writings about systems-engineering theory. Doing so will reveal what Chinese engineers and strategists may have divined from these writings, what dangers the metasystems approach poses for the allies, and what opportunities it presents them to exploit.

One of my favorite articles about systems-of-systems engineering appeared in Engineering Management Journal this time in 2003, courtesy of a team of scholars at Old Dominion University in Norfolk, Virginia. It’s worth your time. Here are a few takeaways I gleaned from it that seem relevant to U.S.-China strategic competition. First of all, metasystems engineering poses a tough intellectual challenge. Engineering a standalone complex system is hard enough. My own background is in gunnery and marine engineering. Think about an old-school steam engineering plant. A main engine connects to a shaft that turns the screw and impels the ship’s hull through the water. Simple. But it takes boilers to generate the steam that supplies the motive force to run the engine. And boilers need constant supplies of fuel and freshwater, as well as auxiliary systems to condense exhausted steam back into freshwater for reuse and to perform other services around the margins. That demands a host of pumps, heat exchangers, and on and on. Go below the next time you visit a historic ship and prepare to be bewildered by interlocking piping systems, valves and sundry contraptions.

You might say that even a freestanding weapon system or platform is a system-of-systems. Now try operating a variety of dissimilar systems in concert with one another for tactical and operational effect. The ODU coauthors cite a 1979 book likening a system-of-systems to “a jigsaw puzzle that is about five miles across.” Rather than looking down on the puzzle from aloft to see how to arrange the pieces, “we are standing on the ground trying to see how to fit it together.” It’s hard to see the whole from ground level, especially since our visual horizon is limited. Nor, they go on to suggest, do the puzzle pieces constituting a system-of-systems fit together neatly. Just the opposite.

Second, writings about systems-of-systems are abstract in the extreme. They impart little sense of the surroundings where metasystems do their work. Ripping things out of context may be unavoidable given the sheer variety of complex systems that military services must mix and match to prosecute operations. The Old Dominion team starts out promisingly—they even cite the aircraft-carrier task force as an example of a metasystem—but then lapse into abstractions for the rest of the article. There’s more concreteness to the DOD Systems Engineering Guide and the Chinese writings surveyed in Engstrom’s RAND monograph, but not enough to give readers much sense of how to put system-of-systems theory to practical use. The chasm between theory and practice could pose a weakness for friendly use of the concept, as well as a frailty to exploit in hostile metasystems should a foe fail to knit its systems together tightly enough.

Third, analysts and practitioners treat systems-of-systems almost exclusively as an engineering challenge. One jargon-laden DOD definition of the phrase depicts overseeing metasystems as “an interdisciplinary engineering management process that evolves and verifies an integrated, lifecycle balanced set of system solutions that satisfy customer needs.” Surveying the literature reveals that proponents of the concept likewise regard it overwhelmingly as an engineering problem. The nonengineering disciplines referred to by the adjective “interdisciplinary” are STEM disciplines—mathematics and the physical sciences for the most part. (The Purdue College of Engineering, which runs a program on this topic, does allude to bringing sociology into the mix.) The ODU coauthors, by contrast, espouse a “transdisciplinary” approach that shreds traditional academic boundaries.

And that makes sense. Systems-of-systems do their work beyond the purely scientific-technical realm, don’t they? Generally speaking, engineering systems prefer steady-state operations. They dislike transients. And they especially dislike operating conditions prone to changing around them, as the strategic environment does. Machinery is designed to perform routine tasks the same way, over and over again. Rejiggering or reinventing a machine amid fluid circumstances poses daunting challenges indeed. That’s doubly true when opponents are out there deliberately trying to cause our system to malfunction to their own tactical or operational benefit.

In short, there are perils to viewing a system-of-systems like a carrier task force or an air-force expeditionary air wing entirely as a creature of engineering. Doing so suggests that assembling and operating a metasystem is a scientific endeavor governed by the rational rules that apply to laboratory or field trials. Yet systems-of-systems deploy in mercurial settings pervaded by chance and uncertainty, dark passions, and thinking foes bent on thwarting our will. The context is nonrational. Paradoxical logic—not the linear logic of engineering systems built for steady-state operations—prevails on battlegrounds. Much as Carl von Clausewitz notes, warfare represents a composite of science and art—but the grandmaster of strategy proclaims that getting your way in chaotic surroundings demands more art than science from commanders.