The founder of an influential veterans group neatly summed up the challenge now facing congressional leadership after President Donald Trump made Veterans Affairs Secretary David Shulkin's departure official on Wednesday.

"Firing a VA secretary is easy compared to finding someone who can effectively do the job,'' said Paul Rieckhoff, founder and CEO of the Iraq and Afghanistan Veterans of American (IAVA) service organization during a CNN interview this week. The Senate, which must confirm Shulkin's replacement, must take its responsibility to find a well-qualified new leader seriously and if necessary say no to Trump's pick — the president's little-known personal physician, Dr. Ronny Jackson.

This is not the time to rubber-stamp Trump's pick simply to protect an embattled president. More than 20 million veterans depend on the VA for medical care and other benefits. The department is one of the federal government's largest, with a $186 billion yearly budget and a staff of 360,000.

Running it would be formidable for a seasoned executive in the best of times, which is why previous secretaries have often been hospital administrators or private-sector CEOs. But Jackson, a U.S. Navy rear admiral, appears to have scant management experience. Nor is this the best of times at the VA.

The department is slowly righting itself after a 2014 scandal over appointment wait-times. Constant turmoil at the top doesn't help. If Jackson is confirmed, he will be will be its fourth leader in the past four years. The wait-time scandal led to the resignation of VA Secretary Eric Shinseki. Former President Barack Obama replaced Shinseki with former Procter & Gamble CEO Bob McDonald. Trump replaced McDonald with Shulkin and now has fired him.

"I am deeply concerned,'' said Rep. Tim Walz, a Minnesota Democrat who is the ranking member on the U.S. House Committee on Veterans' Affairs and a gubernatorial candidate. "Stability is the number one concern at any organization.''

Politics will exacerbate Jackson's challenge, should he be confirmed, to hang onto this job. Walz said that moving too slowly on a controversial push to "privatize" the VA medical system was a key reason for Shulkin's ouster, though a travel scandal also contributed. Jackson will face immense pressure from the White House to rapidly pursue this unpopular private overhaul, leading to backlash from influential veterans service organizations opposing it.

While definitions of "privatizing" vary, embracing it could significantly siphon off resources or even dismantle the system of specialty medical centers that has provided care and research into veterans' unique medical needs for decades. Veterans should have additional private care options, but this must be in addition to, not in place of, a robust VA medical system.

Veterans agree. Very few of those polled in a Veterans of Foreign Wars (VFW) survey released last year wanted to outsource the VA's mission to private-sector clinics and hospitals. Instead, 92 percent said keep the VA and fix its deficiencies.

Congress ought to keep that in mind as it weighs Jackson for the VA top job. Is he there to serve veterans? Or is he there to undermine this nationalized health care system for ideological reasons? If privatization is Jackson's mission, he ought to be asked for evidence that privatization would do what its proponents say it will: save money and deliver better care. A new program based on this approach, called Veterans Choice, has proven costlier than expected and generated complaints that wait-times for care are even longer than going through traditional VA avenues.

If Jackson gets the job, Walz correctly points out that everyone should want him to succeed "spectacularly." Our veterans' health and well-being depend on it. But it's unclear, at best, how a doctor best known for delivering a glowing if logic-defying report on Trump's health could possibly be the right person to lead the VA at this critical time.