Covering up Chinese espionage at NASA?

Washington Examiner:

Congressional leaders are challenging a U.S. Attorney's denial that the Justice Department shut down a federal espionage investigation involving the illegal transfer of U.S. space defense weapons technology to foreign countries, including China, The Washington Examiner has learned.

Melinda Haag, the U.S. Attorney for Northern California, also denied that she had ever requested authority to prosecute anybody as a result of the espionage investigation.

But Sen. Charles Grassley, R-IA, and Representatives Lamar Smith, R-TX, and Frank Wolf, R-VA, say Haag's denials don't square with evidence they've reviewed and they wonder if Justice Department or White House officials interfered with a potentially explosive espionage investigation or if "politics played a role in the prosecutorial decisions made in this case."

"Your statement conflicts factually with information we received from federal law enforcement," Wolf, Smith and Grassley said in letters sent today to Haag and Assistant U.S. Attorney General Lisa O. Monaco questioning the abrupt end to an FBI national security investigation and grand jury probe.

At the center of the controversy is cancellation of a national security probe once led by Assistant U.S. Attorney Gary Fry. Frustrating attempts by foreign powers to steal U.S. space weapons technology have long been priorities for the FBI, the Department of Homeland Security and NASA's Inspector General.

The technology reportedly involves U.S. weapons capable of operating from space to defend the United States against international ballistic missile attacks.

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There is more.

Dropping such an important investigation makes no sense, at least on the surface.  What is the administration trying to avoid?  Could they at least threaten the Chinese with some future regret for stealing our secrets?