TROIA, Portugal — NATO troops tested their collective power here on Thursday in a large demonstration of beach storming force, which could serve as precursor to a more robust presence around the Mediterranean as the alliance begin to focus on its southern flank.

Trident Juncture, one of the largest NATO exercises since the end of the Cold War, ended with a flourish as U.S. Marines moved from sea to land in the first large-scale tryout of a new Corps effort that puts American quick strike forces aboard NATO-allied ships.

“NATO is adapting to a new reality,” said Jens Stoltenberg, the alliance’s top official during a stop in Portugal Thursday. “Allies like Portugal, Italy and Spain are on the frontline of the challenges we face to our south.”

For NATO, the focus on maritime quick strike capabilities comes as allies examine how to enhance their presence around the Mediterranean, where Russia has a growing naval presence. In December, NATO foreign ministers are expected to meet in Brussels to sketch out more plans to bolster NATO’s posture in the south, where Russian activity as well as instability stretching from north Africa to Syria, pose challenges for allies in Europe.

NATO is looking at various ways to improve its situational awareness in and around the Mediterranean, with plans to increase its drone presence in southern Italy, NATO officials have said. NATO Supreme Allied Commander Gen. Philip Breedlove also has stated he wants more U.S. Navy presence in the Mediterranean as a counter to recent Russian moves.

Meanwhile, allies also will continue to look for ways to increase its presence in the Baltics and eastern Europe, where NATO has sought to enhance its presence as a means for reassuring allies and sending a deterrent signal to Russia.

“NATO has to be able to defend any ally against any threat. We are able to d that today, but we have to also recognize the world is changing and therefore NATO has to adapt,” Stoltenberg said. “And now we are addressing the challenge of what we call long-term adaptation.”

In Portugal, dozens of dignitaries, including Portuguese President Aníbal Cavaco Silva and NATO Secretary-General Jens Stoltenberg, gathered to watch as the combined force of U.S., Portuguese and British Royal marines stormed the beaches of this normally quiet resort town.

They were joined by military officials from across the alliance in observing the final military operation of the three-week Trident Juncture exercise.

Hopefully, they didn’t blink.

In less time than it takes to drink a cup of coffee, the integrated Marine force had launched from the British HMS Bulwark and the Spanish Castilla and “captured” the beachhead. Ship-to-shore, the entire operation lasted less than 15 minutes.

With the beach secured, Trident Juncture — which involved 36,000 troops from 35 nations — came to a de facto close. Friday is the official end date, but the Marine beach assault was the last in a string of military war games that took place over the final week of the exercise.

On Wednesday, a multinational air and ground force in Zaragoza, Spain, showcased NATOs brute strength in an all-out mock town assault involving tanks, attack helicopters, fighter jets and more than a thousand shock troops.

Trident Juncture involved the first major tryout of the U.S. Marines’ Allied Maritime Basing Initiative under which an American, aviation-based quick response force is placed aboard a NATO-allied ship.

Four MV-22 Ospreys from the Special-Purpose Marine Air-Ground Task Force Crisis Response-Africa have been aboard the Spanish assault ship Juan Carlos I for the past several days. A similar group of Marines lived aboard the British flagship HMS Ocean.

The U.S. recently reached a deal with Spain to increase the Marine presence to 2,200 troops at Moron Air Base, the home station for the Corps’ crisis response force in Europe. The unit, formed less than a year after the deadly 2012 attack on the US consulate in Benghazi, Libya, is a linchpin to U.S. efforts to speed up crisis response time.

By integrating U.S. Marines more closely with allies and utilizing foreign vessels for operations, there is the potential to extend the reach of U.S. Marine forces in the region. Trident Juncture was one step in that direction, according to Marine Forces Europe and Africa commander Maj. Gen. Niel Nelson.

“I think we’ve overcome challenges,” he said. “I think what we’ve done now with the interoperability is that we can do this, we can make this happen and there is a cooperative effort right now to bring it all together.”

Stars and Stripes reporter John Vandiver contributed to this report.

darnell.michael@stripes.com

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