The U.S. Army, its allies and partners have multiple strategic engagements in each other's nations to highlight their capabilities, build partnerships and enhance cooperation throughout their regions.

On September 11th 2001, one such engagement, the Pacific Armies Chief Conference/ Pacific Armies Management Seminar, known simply as PACC and PAMS was underway in Malaysia. Gen (ret.) Eric K. Shinseki was serving as the Army Chief of Staff and the event co-chair on the other side of the world from where attacks on the U.S. homeland were beginning to unfold.

"One of two events in my lifetime I think I'll always remember where I was. The first would be the assassination of President Kennedy, and the other was the 9-11 attacks," Shinseki said.

"We were at an evening reception in Kuala Lumpur with the other Chiefs of Defense, hosted by the Minster of Defense. I recall all of us were standing and I was greeting my counterparts when a member of my staff came out to me and said "Chief, you need to come see this."

"I very quickly excused myself and was brought to our onsite operational center in an adjacent room where I saw the first plane's striking one of the World Trade Center towers being replayed on the news. I immediately contacted the Army Operations center in the Pentagon to get an assessment. At this point the first plane looked like a terrible accident."

"As I was having these conversations, another plane struck the second tower. We were watching it live and at that point, we knew it was not an accident. We were under attack. I gave instructions for the Army Staff to stand up the Crisis Action Team and I went out to explain to the other defense chiefs that I was returning to the U.S.," he said.

The conference did continue with U.S. Army Pacific officials remaining behind, while the rest of the senior Army delegation prepared for immediate departure back to the U.S.

Aside from the travel distance between the U.S. and Malaysia requiring stops to refuel and ensure they had a rested crew onboard, Shinseki's staff faced the additional challenge of getting back to the United States U.S. airspace was being closed down.

Amidst the chaos and confusion, for the first time in history, the Federal Aviation Administration grounded all flights over or bound for the continental United States. Some 3,300 commercial flights and 1,200 private planes were guided to airports in Canada and the United States following the attacks.

"We traveled to Guam and to Hawaii, landing at the Air Station, where the Marines facilitated my onward movement with one of their aircraft and crew. About a day later I was back in D.C.," Shinseki recalled. "We didn't get clearance to enter U.S. Airspace until within an hour off of California. I got back got back and immediately joined the flow of treating the injured, finding the missing, honoring those who had been lost, and finding out who had done this."

Fifteen years after their first event was interrupted by tragedy, this year the 40th iteration of PAMS is returning to Kuala Lumpur to be co-hosted by the Malaysian Army and U.S. Army Pacific. In 2001, the theme for delegates to discuss was "The challenges of interoperability in the new millennium", and it focused on transnational threats, multinational approaches to regional security challenges and interoperability in peacekeeping and humanitarian assistance. This year discussions for the over 30 attending nations will be focused on countering violent extremism.

Lt. Col Wendy Cheong, a signal officer and the head of the C4I Detachment for Headquarters, Malaysian Army Field Command West, has her own vivid memories of hearing the news of the 9-11 attacks.

Cheong is currently one of the key planners for this year's event, but in the 2001 PACC/PAMS she was working as a liaison officer.

"It was very sad and frightening at the time. We also have Twin Towers, so to see it unfold and imagining what if that happened here, what are we going to do? It really enhanced our awareness for security and served as a reminder that this could happen to anyone, anywhere," said Cheong.

"It is very important that we maintain the strong relationship we've kept between Malaysia and the US and that we have events like this to exchange ideas, "Cheong said. "Planning PAMS today is very different than it was then, because we have so many new technologies to speed up coordination. But the importance of collaboration on these topics remains the same."

"The 21 chiefs were all prepared for a very important conference. Unfortunately, we didn't get to finish it," Shinseki said. "All these years later what really comes back to me about how that tragedy unfolded was how very clearly my co-host, Gen. Hashim (General Tan Sri Md Hashim Bin Hussein, then Chief of Army, Malaysia) his army at our disposal to ensure the security of 21 chiefs and all our event participants."

Shinseki also recalled his appreciation that, as the senior U.S. delegation was departing, all of the other Chiefs of Defense had gathered in the hotel lobby to personally offer condolences and wish him and the U.S. the best. "Gen. Hashim and the other chiefs were most sympathetic. They knew that life had changed that day for all of us, but certainly for the United States."