WASHINGTON >> Army Col. Kathryn A. Spletstoser says she had returned to her hotel room and was putting on face cream on the night of Dec. 2, 2017, after a full day at the annual Reagan National Defense Forum in California, when her boss, Air Force Gen. John E. Hyten, commander of U.S. Strategic Command, knocked on her door and said he wanted to talk to her.

The military’s itinerary of Hyten’s movements that day in Simi Valley, which was viewed by The New York Times, said he was having “executive time.” Spletstoser said in an interview this week that her boss “sat on the bed in front of the TV and asked me to sit down next to him.”

According to her account, Hyten reached for her hand. She became alarmed and stood back up. He stood up too, she said, and pulled her to him and kissed her on the lips while pressing himself against her, then ejaculated, getting semen on his sweatpants and on her yoga pants.

In April, President Donald Trump nominated Hyten to be the next vice chairman of the Joint Chiefs of Staff. If confirmed, he would become the country’s No. 2 military officer, helping to oversee the 1.2 million active-duty American troops at home and deployed around the world.

Hyten denies Spletstoser’s allegations of being inappropriately touched several times in 2017, and an Air Force official charged with investigating her complaint declined in June to refer Hyten to a court-martial.

A Defense Department official who discussed the investigation only on condition of anonymity maintained that the Air Force’s investigation into the allegations did not unearth any emails, text messages or other supporting evidence, except for the fact that the two were together at each time that she alleges abusive sexual contact took place.

The official said that Hyten, who oversees the country’s nuclear arsenal as the head of the Strategic Command, is one of the most heavily guarded officers in the U.S. military and is frequently escorted by a security detail.

The official said it would be difficult, though not impossible, for the general to have entered Spletstoser’s room without his security guards noticing. None of the guards, the official said, reported anything amiss.

Earlier this week, both the general, who is 60, and his accuser, 51, privately testified before members of the Senate Armed Services Committee, which is considering Hyten’s nomination.

“This is a very serious matter; the accusations are very serious,” Sen. Tammy Duckworth, D-Ill., told reporters after Hyten’s testimony Thursday. “We’re taking this step by step and being as thorough as we can on both sides of the aisle.”

Sen. Jim Inhofe, R-Okla., chairman of the committee, said he planned to go ahead with hearings on Hyten’s nomination.

But the case is, once again, highlighting an issue that has plagued the military as it struggles to address sexual assault complaints within its ranks.

The military’s initial investigation into Spletstoser’s charge was handled by Gen. James M. “Mike” Holmes, chief of Air Combat Command, who technically is junior to Hyten.

“The severity of the allegations and the sensitivity and seniority of General Hyten’s billet demand that a senior officeholder — not a peer, and certainly not a peer who is junior in grade to General Hyten — should be the convening authority,” Sen. Elizabeth Warren, D-Mass., and Duckworth wrote in a June 25 letter to Defense Secretary Mark Esper.

The Pentagon has taken pains to praise Hyten.

Col. DeDe Halfhill, a Defense Department spokeswoman, said that “with more than 38 years of service to our nation, Gen. Hyten has proven himself to be a principled and dedicated patriot.”

The case has drawn the ire of sexual assault victims advocates, who note that the Pentagon has not issued a similar official lauding of Spletstoser, the alleged victim, despite her own 28 years in the Army, including two combat tours in Iraq and two in Afghanistan. She remains on active duty in the military.

Col. Don Christensen, who retired from the Air Force and is president of Protect Our Defenders, which advocates on behalf of assault victims, said even after years of public criticism over how the Defense Department handles sex assault cases, the Hyten case shows that the agency still has not gotten it right.

He pointed to the case of Sen. Martha McSally, R-Ariz., as an example.

Earlier this year, McSally announced that she was raped while she was a cadet at the Air Force Academy 30 years ago. She did not disclose who raped her but said that the Defense Department’s handling of her case made her feel as if she were being raped again.

Still, McSally said she believed the prosecution of such cases should remain within the purview of the Defense Department, a position the Pentagon takes as well.

“It just hit me the differences in the way the military addressed Senator McSally’s disclosure and the way they are dealing with Hyten’s victim,” Christensen said in an interview. “McSally disclosed she was raped by an unnamed superior officer at an undisclosed time and undisclosed location 20 years after she was raped. McSally received an official apology from the Air Force.”

Spletstoser, by contrast, told the Pentagon “who it was, when it occurred and where it occurred,” Christensen said. “She cooperated fully with the investigation and agreed to testify” before the Senate committee.

“She has received no apology,” Christensen said. “Instead, the Pentagon praised the man she says sexually assaulted her.” He added: “If this were Staff Sgt. Hyten, he’d be getting charged. The only reason he wasn’t charged is because he’s Gen. Hyten.”

In April, after Spletstoser reported the confrontation in her hotel room, the Air Force’s Office of Special Investigations opened an inquiry into whether Hyten had committed abusive sexual contact. Its review, parts of which were viewed by The Times, includes a redacted interview with Hyten’s wife, Laura Hyten, in which she says her husband took a lie-detector test administered by a private company and was upset afterward because “it did not go well.”

The report says that Laura Hyten later “clarified she did not mean that the polygraph did not go well but rather she understood that the results were inconclusive.” John Hyten declined to take a lie-detector test for the Defense Department’s investigation, two Defense officials said. Spletstoser said that she was not asked to take one.

At the Strategic Command, based in Omaha, Nebraska, Spletstoser has a reputation for being hard-hitting and assertive, traits that she freely acknowledges. An administrative inquiry in 2018 includes statements from her colleagues at Strategic Command that she was “toxic” in her dealings with both subordinates and superiors.

“Col. S. says things in meetings that could be perceived as disrespectful to senior officers and civilians,” the administrative inquiry quoted a rear admiral as saying. “I have not seen Gen. Hyten correct her bluntness nor interruptions to seniors.”

In fact, Hyten was hugely complimentary in her performance reviews she provided to The Times, including one that was dated Nov. 14, 2017 — just weeks before the alleged incident in Simi Valley but after what she said were other unwanted sexual encounters that he initiated.

That review, in which Hyten was listed as the senior rater, described Spletstoser as an “exceptionally competent and committed leader with the highest level of character” and added that “her ethics are above reproach.”

In her interview this week, the first time that she has agreed to be publicly identified in the case, Spletstoser said that she had gone back to her colleagues after seeing their comments and “tried to apologize to people for how I behaved.”

But none of that takes away, she said, from what she says her boss did to her over the course of 2017.

On several occasions, Spletstoser said, Hyten tried to kiss her, hug her and touch her inappropriately while in her office or on trips. She said she told him no, and even threatened to tell his wife, and that he was often apologetic and emotional afterward.

The unwanted touching continued, she said, escalating to the alleged Simi Valley assault in December 2017.

The festive two-day port of call passes for the glitterati of the military policy wonk world. American lawmakers and former Cabinet officials receive “peace through strength” awards, while panel discussions on the Islamic State, combating Russia and China, and how to engage with Silicon Valley unfold on the stage before participants head to the hotel bars.

Spletstoser said she was appalled after Hyten ejaculated while pressing up against her, and she went into her hotel bathroom and threw a towel at him, telling him to clean himself up.

He went into the bathroom and stayed there for several minutes, she said. When he came out, he was again apologetic and asked her if she would report him.

“I was distraught,” she said. But “who was I going to report it to? Secretary Mattis? Really? All I was trying to do was just survive and not have my life ruined.”

Spletstoser said that she had believed that Hyten would retire and had planned to say nothing about the incident.

When he was nominated to the second-highest military job in the country, she said, “I realized I have a moral responsibility to come forward. I could not live with myself if this happens to someone else and I didn’t do anything to stop it.”