Many things are better in theory than practice: Eating an ice cream cone while driving, running for president, walking twenty miles a day to stay fit. Now add to that list an op-ed by Bruce Gilley in the New York Times, “The Rise of the Middle Powers.”

The nugget of Gilley’s piece is this: “As China’s influence grows, the United States is struggling to come up with an effective strategic response. . .Through proactive and nonaligned diplomacy, middle powers may be able to influence the rise of China in ways the United States cannot.”

Fair enough, but who are these so-called “middle powers”? Every analyst seems to have his own definition, and that is where the trouble begins for Gilley. He defines them to be “the 10 or 20 influential states, like South Africa and Australia, that aren’t permanent members of the UN Security Council or global giants.” Okay, but who else makes his cut? Countries as disparate as Ghana, Egypt, Sweden and Bangladesh.

The author claims that pursuing middle-power options “on conflicts like the South China Sea and Syria would mean allowing friendly countries to take the lead on diplomatic work, because they are less threatening to China. While this may entail some compromises for Washington,” Gilley says, “it is more likely to generate solutions that Beijing will heed.”

And yet, herein lies the problem: What use is a solution that Beijing will heed if it’s not necessarily what we want? Gilley’s motley middle powers have complex demographic, governmental and societal differences that make them hugely varied, not to mention they are of contrasting economic strengths. Some may share similarities and alliances with the United States, but each has its own goals and agenda. The “compromises” for Washington in any given case could change dramatically depending on which middle power was in charge.

The notion that Washington should occasionally take a backseat to regional powers is certainly not new nor is it in poor judgement. Yet it’s clear that in this case, Gilley needs to narrow his definition of middle power before we can employ U.S. diplomacy in the manner he envisions.