Some 800 infantry soldiers and a Navy aircraft carrier are bound for Haiti to aid the massive relief effort under way, the first major influx of U.S. troops since the catastrophe struck.

The troops, expected to arrive on Friday, were a clear sign that President Barack Obama was intent on rescuing the ravaged nation, despite the strain that such a vast undertaking would invariably take. “To the people of Haiti, we say clearly and with conviction, you will not be forsaken,” Mr. Obama said. “You will not be forgotten. In this, your hour of greatest need, America stands with you.”

Military personnel began trickling into Haiti on Wednesday to restore operations at the airport and join the relief effort. An early assessment team has outlined an urgent requirement for helicopters to ferry supplies and victims, as well as equipment to purify water and clear road debris.

A primary challenge is the badly damaged seaport that will make it difficult for ships - carrying the kinds of mass amounts of supplies and helicopters needed in a natural disaster - to offload their equipment. Likewise, the small airport at Port-au-Prince was described as congested and chaotic with civilian flights cancelled and planes stranded without the ability to refuel.

On Thursday, the Army sent about 100 soldiers from the 82nd Airborne Division to set up tents and prepare other necessities for more troops on their way. As many as 3,500 troops from the division’s 2nd Brigade were expected by Monday with some 2,200 Marines also en route. Meanwhile, the Navy dispatched several ships, including the USS Carl Vinson. The aircraft carrier, based in Norfolk, Virginia, was expected to bring some 19 helicopters.

“By the end of the day, we will have a significant military presence (in Haiti) that will continue to grow from there,” said Pentagon spokesman Bryan Whitman.

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