CNN national security analyst John Kirby, a retired rear admiral in the US Navy, was a spokesman for both the State and Defense departments in the Obama administration. The opinions expressed in this commentary are his own. View more opinion articles on CNN.

(CNN) Lt. Col. Alexander Vindman was right when he spoke to his father —who had emigrated from then-Soviet Ukraine to the United States — in those gripping opening remarks to his testimony before the House Intelligence Committee's impeachment hearings last November:

He will be just fine.

Here is what Vindman, the top Ukraine expert at the National Security Council who was fired by President Donald Trump Friday said at the hearing:

"Dad, my sitting here today, in the US Capitol talking to our elected officials is proof that you made the right decision forty years ago to leave the Soviet Union and come here to United States of America in search of a better life for our family. Do not worry, I will be fine for telling the truth."

Vindman did his duty by not only testifying about the infamous July 25, 2019 White House phone call, in which Trump pressed Ukrainian President Volodymyr Zelensky to investigate Trump's leading 2020 rival Joe Biden, Burisma (the Ukrainian energy company that had hired Hunter Biden), and the 2016 election--while $391 million in congressionally approved military aid was being withheld.

But Vindman also had the gumption to speak out after an earlier July 10 White House meeting. There, he testified, the now-fired US ambassador to the European Union, Gordon Sondland, directly pressed Ukrainian officials to launch specific investigations in exchange for a meeting with the President.

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Vindman related his concerns about both meetings to the NSC Counsel.

Indeed, Vindman would have been derelict in that duty had he not spoken out.

He told a truth that was inconvenient but corroborated by many others.

He did not fold under the pressure or complain or cower, either in his appearance before Congress or afterward.

He went right back to work, as did his brother Yevgeny Vindman, a lieutenant colonel who also worked on the NSC staff. He did not testify, but was also fired Friday.

In fact, the only thing Alexander Vindman might be fairly accused of is naivete, if he really believed somehow that he could stay in his job and keep supporting our Ukrainian policy, such as there is one.

He had to know deep down that he could never have been warmly received back into the toxic environment at the White House. Even co-workers friendly to him and sympathetic to the incredibly difficult position into which he had been thrust could be forgiven for feeling the chill of the vitriolic reactions, statements and tweets of President Trump after Vindman's testimony.

No, it is not the Vindman brothers who have been disgraced by this pettiness. It is President Trump.

It is not they who will be remembered for putting personal needs above national interests. The President will.

And it is not they who will in years to come be forced to qualify or explain or argue the case surrounding their behavior.

In a final and outrageous act of vengefulness, White House security officials escorted the Vindmans off the grounds.

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Unlike that of so many others in this sad saga, the Vindmans' conduct was unimpeachable.

The Secretary of Defense told reporters Friday that all service members would be welcomed back to the Pentagon and to the Army, and that they need not fear retribution of any kind. The vice chairman of the joint chiefs of staff also made it clear that Alexander Vindman's skills would find a new home back in military ranks. He is apparently on track for a service college stint , appropriate for his time in service.

He should look forward to this reassignment and to this new educational opportunity. I hope he proves willing to share with his fellow students the lessons of his trying experience.

Alexander Vindman has seen the inner workings of the National Security Council, no matter how dysfunctional it may be at times. He has advised senior leaders on how best to manage one of our most important bilateral relationships, no matter how much some of those leaders chose to ignore that advice. And he left that position with his honor intact, no matter how hard the President might try to dismantle it.

There's an awful lot there to learn from.

You know, on second thought, maybe Alexander Vindman was wrong. He's not just going to be fine. In the long run, I believe he and his brother will be better off for it all.

Better to be back with the Army they love.

Better to have upheld their oath to the Constitution.

Better to have maintained their integrity and dignity under severe test.

And better for being able to sleep soundly at night, knowing they did their duty.

There will continue to be criticism from the President's supporters. Sadly, the Vindmans cannot avoid the calumny which will be leveled at them. I don't doubt for a moment that their lives will not return to normal any time soon, or that they won't still harbor concerns over their safety or that of their loved ones.

It's a high price to pay for character. Perhaps too high. But in that very purchase, their family members will no doubt be better off as well.

A new example of moral courage now lies before them.

Frankly, we should all feel better off for that.