Trying this question again.
A few years ago, there was a post asking about the design philosophies behind Cold War submarines. Was there a similar difference in design philosophy between the Americans and Soviets when it came to designing fighter planes? Or were they going after the same thing with, say, the F-4 and MiG-21?
There is one classic comparative article on Soviet-US fighter planes: Leon Trilling, "Styles of Military Technical Development: Soviet and U.S. Jet Fighters — 1945-1960," in Everett Mendelsohn, et al., eds., Science, Technology and the Military (Springer, 1989).
Trilling's argument is that they basically were attempting to achieve the same technical ends, more or less. This is because they were, of course, meant to be fighting against one another, and so were in a deliberately "mirrored" dynamic.
The main differences that Trilling identifies are doctrines about production and maintenance. The US approach could be summarized as bleeding-edge-at-whatever-cost. Which is to say, that the US priority was on gaining slight quantitative advantages, even if they came at significant expense in both production and maintenance.
The Soviet philosophy, by contrast, emphasized mass production, relative economy, and interchangeability. The Soviet planes had to be serviceable with existing bases and tools, and while they also sought to be competitive with American planes, they were more willing to sacrifice the quantitative measurements if it meant they could have more planes and could more easily integrate them into their existing production and maintenance infrastructures.
The differences, of course, are mirrored in the differences between their military-industrial complexes. The US MIC was dominated by corporate contractors who found that the money spigot was easily turned on if there was a promise of technological superiority, a remnant of American visions of their victory in World War II. The Soviet design bureau system by contrast was far more bureaucratic and centrally planned, and while the Soviets expended quite a lot of resources of their own, they found themselves always far more tight on that end than the United States. It is a dynamic that one saw in many technological areas of competition during the Cold War, from the lowly infantry rifle (the M-16 vs. the AK-47), to something as massive as a nuclear reactor (the RBMK was a product of these same forces, and was adopted in part because of its ability to be easily assimilated into the existing production economy).