djibouti unite state closely watch recent increase piracy coast somalia senior u.s. military official say sunday defense secretary jim mattis visit important military base djibouti rise piracy attack least partially drive famine drought region top u.s. military commander oversee troop africa say mattis visit part week-long trip middle east africa unite state use base djibouti tiny country size wales southern entrance red sea launch pad operations yemen somalia sudden string attack somali pirate come years without report incident attack peak 237 2011 decline steeply ship owners improve security measure international naval force step patrol month see new rash attack two ship capture third rescue indian chinese force crew radio help lock safe room bottom line half dozen incidents marine general thomas waldhauser say press conference stand alongside mattis ready say trend yet continue watch say add one reason increase famine droughts region since vessels target carry food oil accord u.n. world food programme 20 million people nigeria somalia south sudan yemen risk die starvation within next six months south sudan alone 100,000 people suffer famine million brink starvation mattis add situation watch expect u.s. military response surge piracy u.s. defense official speak condition anonymity say international ship company start become complacent security could also help explain rise piracy incidents djibouti strategically important route suez canal barren nation sandwich ethiopia eritrea somalia also host japanese french base u.s. base 4,000 personnel locate miles chinese one still construction cause concern u.s. officials mattis visit base come unite state increase pressure militant group al shabaab region white house recently grant u.s. military broad authority strike al qaeda-linked al shabaab militants somalia waldhauser tell reporters yet use new authorities give white house al shabaab able carry deadly bomb despite lose territory african union peacekeepers support somali government sunday military vehicle hit roadside bomb somalia semi autonomous puntland region sunday kill least six soldier injure another eight unite state recently send dozen troop somalia help train members somali national army also carry strike yemen al qaeda arabian peninsula aqap aqap boast one world fear bomb makers ibrahim hassan al-asiri persistent concern u.s. government ever since 2009 attempt blow detroit-bound airliner christmas day u.s. watch piracy increase somalia see tie famine