Norman Eisen and Asha Rangappa

Opinion contributors

President Donald Trump's legal team appears to have won a victory. Special counsel Robert Mueller has agreed to let Trump provide answers in writing, instead of in a personal interview, to questions concerning his campaign's contacts with Russia. But far from a defeat for Mueller, this is part of a carefully considered approach that has been repeatedly vindicated.

Since January, Mueller and his team have reportedly been talking with the president’s lawyers about securing his testimony. By dragging out the negotiations, Mueller has allowed breathing room for the rest of his investigation. And he has put that time to good use.

Mueller has charged 12 Russian military intelligence officers with hacking Democratic National Committee emails; reached a plea deal with Rick Gates, Trump’s former deputy campaign manager; sentenced George Papadopoulos, the campaign’s former foreign policy adviser; and reached a cooperation agreement with former campaign manager Paul Manafort after convicting him on eight criminal charges.

By all accounts, the end is nowhere in sight. Mueller is like Shakespeare's Birnam Wood, creeping closer to the White House step by step, without the president fully realizing it.

Delays bring more Trump tweets, more evidence

Mueller has given up very little in buying that time — and in agreeing to accept written answers from Trump. The reported offer only covers questions about possible collusion. On that front, Mueller may already have enough evidence without Trump's testimony, especially now that he has cooperation from Manafort and reportedly from Trump's Mr. Fix It, lawyer Michael Cohen.

Neither does the delay likely affect Mueller’s obstruction of justice case, given the amount of already known evidence pointing to Trump’s corrupt intent in firing former FBI Director James Comey. At this point, Mueller has contemporaneous notes from Comey’s conversations with the president, in which he asked for “loyalty” and for the FBI to let go of its investigation of former national security adviser Michael Flynn (who has pleaded guilty to making false statements and will be sentenced Dec. 18).

Mueller also has the president’s own admission on national television that he fired Comey because of the "made-up" Russia story. And Mueller has had numerous unfettered interviews with White House counsel Don McGahn — who knows of Trump’s efforts to stop Attorney General Jeff Sessions from recusing from the Russia investigation, and may have more information about Trump pressure on the intelligence community to officially clear his name.

Nor has Mueller given up his ultimate weapon. He could, if he chooses, issue a subpoena to compel the president to testify. By building a paper trail that shows he has tried everything in his power to obtain the president’s voluntary cooperation, Mueller is strengthening his case if it ever does go to court.

In the meantime, the delay could even help add to Mueller’s obstruction case against the president. With every angry tweet that rails against the Russia probe, Mueller or his own attorney general, Trump adds to Mueller’s gallery of exhibits showing Trump’s “corrupt” intent to quash the Russia investigation.

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The protracted negotiation with Mueller, moreover, provides a specific issue for the president to focus on with his lawyers and a channel for him to vent his frustrations. Allowing the president to believe he is calling some shots and pushing back on the investigation gives Trump the illusion of control and makes him less likely to panic, lose his temper, and impulsively try to fire Mueller or his boss, Deputy Attorney General Rod Rosenstein.

We may well have seen the beneficial results in the past few days. Despite a New York Times report that Rosenstein urged actions harmful to the president, a much feared Saturday Night Massacre II did not materialize. The claims — that Rosenstein offered to wear a wire around Trump and brought up the 25th Amendment — smack of spin by someone making mischief.

Still, Trump’s response has been surprisingly muted (so far), perhaps in part because Mueller and Rosenstein have avoided pushing the president into a corner (yet). The result: Despite constant rumors of Trump intending to fire one or both, they are still here.

The truth is that with the Nov. 6 elections so close, Trump’s hands are tied. He can’t fire either of them without risking a backlash and further helping Democratic candidates. No less a provocateur than Fox News’ Sean Hannity went on the air Friday after the Rosenstein allegations to beg the president, don't fire people now. Mueller’s cautious approach has helped bring us to this point.

Russia report release more likely after midterms

Stalling on the interview since January has also placed Justice Department officials in an advantageous position regarding Congress. Under the special counsel regulations, Mueller does not have the authority to issue a report directly to Congress, and is required to submit his report to Rosenstein. Today, Rosenstein would be submitting such a report to a Congress controlled by Republicans who would not be eager to release it to the public.

However, with the midterm elections in six weeks, Democrats stand a strong chance of winning a House majority. That means Democrats would control the House subpoena power and could ensure that Mueller’s findings see the light, even in the event Rosenstein or Mueller is fired.

While the president’s revolving door of lawyers has been occupied protecting the president from himself, Mueller has been playing the long game. What Trump’s legal team considers a victory is a deliberate strategy by Mueller to continue kicking the can down the road and making sure the investigation — and his and Rosenstein’s jobs — survive the process.

Norman Eisen is a senior fellow at Brookings, chair of Citizens for Responsibility and Ethics in Washington and the author of "The Last Palace: Europe’s Turbulent Century In Five Lives and One Legendary House." Asha Rangappa is a senior lecturer at the Yale Jackson Institute for Global Affairs and a former FBI special agent. Follow them on Twitter: @NormEisen and @AshaRangappa_