The Donald Trump Pentagon, in so many words, is saying that the Obama administration’s decision to waive punitive sanctions and buy combat helicopters from Russia was a bad deal.

The Pentagon’s first congressionally required report on Afghanistan under President Trump says the Russian Mi-17 chopper has proved a failure in the long war and will be phased out in favor of American-made UH-60 Black Hawks.

The Obama administration came to realize the failure in its last weeks in office and stopped the deal.

The report this month on “Enhancing Security and Stability in Afghanistan” marks official confirmation that the Russian model broke down too often for the Afghan air force logistics system to keep up.

“Along with the increased expense and difficulty in maintaining the Mi-17 helicopter fleet, utility helicopters are in high demand and the required maintenance exceeds current capacity and capability, leading to maintenance backlogs and a reduced number of aircraft available,” the Defense Department report said. “Included in the recapitalization effort is an initiative to transition the force away from Russian-made Mi-17 helicopters to more reliable, cost-effective, and easier to sustain U.S.-made UH-60 helicopters.”

The Mi-17 stood as an outlier in President Obama’s economic-sanction-filled assault on the regime of Russian President Vladimir Putin in response to his invasion of eastern Ukraine.

The administration allowed Rosoboronexport, the state-run arms broker, to stay off the sanctions list as it pertained to maintaining Mi-17s amid $554 million in U.S. funds via Afghanistan to supply the helicopter. The argument for the full deal was that Afghan pilots and crew members were more accustomed to Russian-made weapons systems.

In an era in Washington where any and all contacts with Russia by any Trump-connected person fetches intense media and Democrat scrutiny, the Obama administration showed that sometimes the political situation dictates that Washington must deal with Moscow.

Meanwhile, Moscow has lent credibility to the brutal Taliban insurgency by arguing that it is fighting the Islamic State terrorists anchored in Afghanistan.

The Obama administration’s last Pentagon update on Afghanistan in December did not announce an Mi-17 cancellation or procurement of the U.S. Army workhorse UH-60.

In fact, the administration seemed to have a love-hate relationship with the Mi-17, praising its ability to perform cargo and combat missions “for which it is uniquely designed.”

But further reading revealed the helicopter, of which 46 are operational in Afghanistan, was growing increasingly unreliable. Logistics centers outside Kabul were not equipped to keep up, creating a timeline that would put all Mi-17s out of action in a few years.

“At the current attrition and flying hour rates, the number of [Afghan air force] Mi-17s available for 2017 will be significantly diminished, and the Mi-17 fleet will become unsustainable by mid-2018, virtually eliminating the AAFs vertical transport and lift capability,” the December report said.

At a press conference that month at the Pentagon, Army Gen. John W. Nicholson Jr., the top U.S. commander in Afghanistan, said Russia has “overtly lent legitimacy to the Taliban.”

“This public legitimacy that Russia lends to the Taliban is not based on fact, but it is used as a way to essentially undermine the Afghan government and the NATO effort and bolster the belligerents,” Gen. Nicholson said.

“And their narrative goes something like this: That the Taliban are the ones fighting Islamic State, not the Afghan government,” he said. “And of course, as I just outlined for you, the Afghan government and the U.S. counterterrorism effort are the ones achieving the greatest effect against Islamic State.”

The four-star general said this year that Russia is providing arms to the Taliban in a direct alliance against the 8,000 U.S. troops stationed there.

Gen. Nicholson defended the original Russia-Mi-17 deal, saying Afghanistan requested the choppers before Mr. Putin invaded Ukraine and before sanctions were imposed as punishment.

Russia is not helping the U.S. plan to keep the Russian aircraft flying until the Black Hawks arrive.

“Keeping the airframe in the inventory but not being able to maintain it would not be positive,” the general said. “And so the Afghan government has gone to the Russians and asked for their assistance in this. The Russians have not provided it.”

The Mi-17 deal was particularly unpopular among members of Congress from Connecticut, headquarters for Black Hawk producer Sikorsky Aircraft Corp.

“I’ll never understand why the U.S. government sent taxpayer money to Russia for helicopters in Afghanistan while Russia was supporting the [President Bashar Assad] regime in Syria and invading eastern Ukraine,” said Sen. Christopher Murphy, Connecticut Democrat.

Today, amid the probes into Russian hacking of the Democrats, Mr. Murphy is a leading advocate of a theory that Mr. Trump and his Trump Organization maintained numerous ties with Moscow.

Perhaps such ties will turn up. To date, there have been reports of some investments by wealthy Russians but no extensive relationship.