Because if it did, we’re going to need more supercomputers (boldface mine):

Sadly for America, the upgraded Piz Dain pushes the Department of Energy’s Titan supercomputer, which is housed at Oak Ridge National Laboratory, into fourth spot. Able to make 17.6 quadrillion number crunches per second, Titan is just a fifth as fast as TaihuLight. In its defense, the U.S. still claims five of the top 10 spots, and it is home to 169 of the supercomputers that make up the fastest 500. China, meanwhile, can only claim 160.

But the news nonetheless serves to highlight America’s decline as a supercomputing heavyweight. This is the first time since 1996 that America hasn’t held one of the top three spots. It indicates that, while it certainly has significant supercomputing resources, it can’t tackle its biggest problems at anywhere near the speeds enjoyed by researchers in China….

Even then, while quantum devices promise to be able to solve some specific problems with incredible speed, it’s not clear whether they will be able to reliably solve all problems faster than regular supercomputers.

That leaves many areas of research currently reliant on the results of huge computational effort—among them drug discovery, materials science, and climate modeling—still in need of fast supercomputers.

The Department of Energy, whose Titan device was once the fastest in the world, is painfully aware of that fact. That’s exactly why it last week announced a $258 million funding injection into its exascale computing project. The money, which will be shared between AMD, IBM, Intel, Nvidia, Hewlett Packard Enterprise, and Cray, is intended to fuel development of machines that are 50 times faster than Titan.

But rich people will get tax cuts and we’ll have an amazing wall, so it’s all good.