After John and other officials left the Pentagon, Robert and several technical experts stayed behind.
"The Martians' civilization legacy" is, of course, an uncertain conjecture. David was actually just using it as an example, with no concrete evidence like the M signal existing.
But what the M Office could confirm was that the space technology burst from New Yuan, or the Chinese people, was abnormal.
Perhaps the Chinese did have geniuses, or they genuinely had exceptional luck, but after the '50s, everyone familiar with cybernetics who had experience managing technological development would notice a problem:
Whether fast or slow, the development of technology is a line—it can be a gentle straight line, or a steep parabola, but it must be continuous, never blank for a while then appearing out of nowhere.
Even the most secretive programs, if traced along their trajectory, could be untangled, and despite minor uncertainties, conclusions could be locked within a certain range.
