The Editorial Board

USA TODAY

The guilty plea of a former Trump campaign adviser and the indictment of two others should put to rest any notions that special counsel Robert Mueller’s Russia probe is —choose your put-down — farcical, "fake news" or a fishing expedition.

In fact, the case against George Papadopoulos is the exact opposite. The onetime foreign policy aide has admitted that he lied to the FBI about his interactions with Russian operatives trying to discredit Hillary Clinton. His plea shows that he was trying to hide something from federal authorities and is now cooperating with them.

Unlike the Papadopoulos plea, the conspiracy case against former Trump campaign manager Paul Manafort and assistant Rick Gates doesn't directly pertain to the 2016 presidential campaign. Both men entered pleas of not guilty on Monday and are entitled to a presumption of innocence. But the charges — that they lobbied in Washington for a pro-Russia party in Ukraine without registering, laundered money for that party, and hid their fees from taxation — raise a number of troubling issues.

REP. FRANKS:Mueller’s reveal is a nothingburger

If the charges are true, the two not only allegedly violated laws for personal profit but also undermined vital U.S. national security interests. In essence, they abetted President Vladimir Putin’s efforts to make Ukraine a Russian puppet state, part of an overall plan to expand his autocratic presence.

To say the least, that is an unusual position for senior aides to a major party presidential candidate to take. According to Mueller's indictment, some of their efforts continued even after Russia unlawfully annexed part of Ukraine, prompting the United States and a host of allies to apply economic sanctions, which Moscow detests, on Putin's cronies.

For Trump, who prides himself on choosing the "best people," to fail so completely in vetting senior aides is astounding. That failure would continue after Trump's election, when he chose the highly conflicted and compromised Michael Flynn as his first national security adviser, an action he was forced to reverse just weeks into his presidency.

Less than six months into Mueller's inquiry, and with other actions likely to come, the special counsel is already proving his worth. The career prosecutor is the one major player who is looking at Russia’s role in the 2016 election from a purely legal, non-partisan and factual perspective.

Yet there are still those calling for his ouster or resignation. One argument holds that his closeness to former FBI director James Comey poses a conflict of interest, as Comey could be a witness. This amounts to blaming Mueller for Trump's highly inappropriate decision to fire Comey, after the FBI director declined to pledge loyalty or go easy on Flynn. It's also a convenient way to impede one potential line of inquiry: that the Comey firing itself constitutes obstruction of justice.

Mueller is a serious man who has brought serious charges. His investigation should not be defunded. He should not step down. He should not be fired. He should — he must — be allowed to do his job without interference.

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