Rep. Ben Ray Luján (D-N.M.) broke a summer lull in Beltway infighting this week by announcing his endorsement of opening a formal impeachment inquiry into President Donald Trump. The August congressional recess had shifted the attention away from the House Democrats' debate over how to proceed after former Special Counsel Robert Mueller's public testimony in July.

Luján's endorsement made news thanks to his membership in the caucus' leadership team — as assistant Speaker, he's the fourth-highest ranking member in the House Democratic caucus. But did it move the ball forward on impeachment? Luján's statement itself points up the difficulties Democrats will have in pressing impeachment with an electorate that seems to have long since tired of debating the 2016 election.

First, if Luján's statement boosted visibility for impeachment efforts during a quiet news cycle, his stated reasons for endorsing such a move arguably did nothing to advance the case. If anything, he made it even more ambiguous by refusing to name specific "high crimes and misdemeanors" Trump may have committed; Luján didn't even mention collusion or obstruction as grounds for the inquiry in his statement.

Instead, Luján cited Trump campaign-worker contacts with suspected Russian intelligence operators, even though Mueller's team specifically repudiated that argument. In fact, the report makes clear that the special counsel's investigators "did not identify any evidence that any Campaign official or associate knowingly and intentionally participated" in any "federal offense arising from Russia contacts."

Even if Mueller had found such evidence against campaign workers, however, that would not provide much reason to impeach Trump himself. Elected officials are politically responsible for the conduct of their campaigns, but not personally legally responsible for crimes committed by others without their knowledge or cooperation. For instance, when illegal campaign contributions from China were allegedly directed to the DNC prior to Bill Clinton's 1996 re-election campaign, no one sought to impeach Bill Clinton or Al Gore for benefiting from the scheme by Beijing to influence that election. Republicans would go on to conduct an ill-fated impeachment effort against Clinton on completely different grounds, but that involved conduct by Clinton himself while in office.

Instead, Luján refers to job performance issues that hardly come close to what most voters would consider legitimate grounds for removing a duly elected president. Trump, Luján accuses, "is abdicating his responsibility to defend our nation from Russian attacks and is putting his own personal and political interests ahead of the American people." If the second claim is an impeachable offense, however, then no president will sit long in office while his opposition controls Congress.

The first claim is vaguely more serious, but it also prompts an uncomfortable situation for Democrats. Barack Obama didn't get the same treatment for actually failing to defend against Russian attacks despite knowing of them well in advance. Further, the lack of effective interference in the 2018 midterms strongly suggests that the Trump administration has improved the situation, although it's certainly worth debating how much is left to do. At its core, Luján's complaint is a policy debate, not grounds for removal from office.

Thus we have the core problem Democrats face after the Mueller report. They had hoped to get a turnkey case of election fraud by Trump himself that would negate the results of the 2016 election. Had Mueller produced evidence to support that conclusion, or even enough to support reasonable suspicion of it, voters would have likely been much more inclined to support impeachment to rectify a fraudulent election outcome. Leading Democrats spent two years making that specific case for impeachment, especially House Intelligence Committee Chairman Adam Schiff (D-Calif.) and Judiciary Committee Chairman Jerrold Nadler (D-N.Y.).

Without any evidence that Trump won the office through foreign influence, however, there's no there there. Nadler wants to pursue obstruction charges related to Trump's temper tantrums, but polls show that voters simply aren't interested in pursuing impeachment on those grounds. In that political environment, Luján's weak and easily refuted argument won't move the needle at all.

So why bother with endorsing an impeachment "inquiry" at at this point? House Speaker Nancy Pelosi has attempted to keep her caucus more focused on policy than impeachment. Democrats will have to show some results from their control of the House as an argument for a return to control in 2021, but they have a rapidly decreasing amount of time in which to accomplish anything. A formal impeachment inquiry, as endorsed by Luján, will eat up almost all of that time — and still fail to remove Trump in the end, which will leave many questioning the point of the exercise.

Voters seem to have already decided it's pointless. Apart from Luján's statement, the public's attention over the Mueller report and impeachment has faded, as The Hill noted on Tuesday. Their interest has focused much more on the 2020 election and the Democratic presidential primaries, which will determine who will challenge Donald Trump for the White House. Voters have the ability to remove Trump from office themselves if they see him as unfit for a second term, and might be asking why Luján and his caucus want to spend their remaining time in this session trying to deny them that choice rather than working on their behalf.