Hand it to Sen. Mark Warner. Of the many Russia-collusion theorists, how many get to claim “bipartisan” credentials?

That’s one question that accompanied Thursday’s supposedly big news that the Senate Intelligence Committee had subpoenaed former Trump lawyer Michael Cohen to testify in February. If anything comes from this appearance—it would be surprising. Senate Intel is the committee Mr. Warner, as ranking Democrat, has turned into the black hole of the Russia investigation, with Republican signoff.

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