A Spanish fishing boat was attacked off the Seychelles this month
The US is using drone spy planes based on the Seychelles to help the island nation fight off Somali pirates.
Seychelles officials say the planes will be used for surveillance, but did not say how many aircraft the US would be stationing there.
Pirates have moved further into the Indian Ocean since international warships began patrolling the Gulf of Aden last year.
The move comes a day after the US gave equipment to Mali to fight insurgents.
BBC Africa analyst Martin Plaut says there is a growing military co-operation between Africa and the US.
He says the Americans will run the drone spy-planes off the Seychelles, and they are planning to fly one mission a day.
Seychelles government spokesman Jean-Paul Adam said everyone agreed that surveillance was key to fighting piracy.
"If you know where they are, you're already half-way towards stopping them," he told the BBC's Network Africa.
In recent years the Gulf of Aden has become the most dangerous shipping lane in the world, prompting several countries to send warships to protect their cargo vessels.
On land, Washington is involved in an ongoing attempt to fight al-Qaeda by working with 10 African states bordering on the Sahara - from Chad to Mauritania.
Offshore the US navy is involved in a continuing programme - sending its vessels to ports in West and East Africa to provide skills to their host nations.
Of course, there are other forms of American military activity that are less public - intelligence gathering that results in targeted strikes against Islamic militants in Somalia are the tip of the iceberg.
But US President Barack Obama's main military effort in Africa relates to training and co-operation - support designed to allow the African military to defend their national interests.
The pirates have been forced southwards, pushing the Seychelles increasingly to the forefront of the battle.
Earlier this year Seychellois officials requested help from the international community to defend their 1.4m sq km of water.
This week France said it would help develop the Seychelles judicial system to ensure captured pirates could be punished.
In September, 23 pirate suspects were released in a swap deal for three Seychellois being held hostage by pirates in Somalia.
France and Spain both have major tuna fishing operations in Seychellois waters and both have come under attack.
A Spanish fishing boat with a crew of 36 was stormed by a pirate gang earlier this month.
Pirates have been able to take advantage of the chaos and conflict that has riven Somalia for years.
The country has effectively had no central government since 1991, allowing gangs to operate almost with impunity and accrue millions of dollars by holding crews to ransom.