Despite the Obama administration's string of foreign-policy successes, commentators inside and outside the US Congress are expressing scepticism about the president's dispatch of troops to help defeat the Lord's Resistance Army.
One concern raised at a US House of Representatives hearing last week involves Uganda's ability to act as an effective partner to the US in the effort to kill or capture LRA leaders.
It was suggested that the deployment of some 7,000 Ugandan soldiers in Somalia may be distracting President Yoweri Museveni and the country's military commanders from the fight against the LRA.
Two high-level Obama administration officials sought to assure members of the House Foreign Affairs Committee that Museveni and the Uganda People's Defence Force are fully engaged in the campaign to destroy the LRA.
Congressman Donald Payne, the Democratic former chairman of the House panel, implied that the United States has an obligation to reciprocate for Uganda's "sacrifices" in battling a US enemy in Somalia.
But a Republican member of the committee pointed out that the US has already spent nearly half-a-billion dollars to improve the UPDF's combat capabilities. And the lawmaker suggested that the Obama administration may be responding disproportionately to a grouping consisting of an estimated 200 to 400 fighters.
Money was much on the mind of the congressional representatives who quizzed Donald Yamamoto, the number-two official in the State Department's Africa Bureau, and Alexander Vershbow, the Assistant Secretary of Defence for International Affairs.
Neither of the officials would say how much the US operation might cost. Vershbow did suggest at one point that the figure would likely be in the "tens of millions of dollars."
Worries were also expressed in regard to the length of time US forces would be deployed in Central Africa and whether they would engage in combat.
Yamamoto and Vershbow declined to give specifics about the mission's duration or military tactics. The roughly 100 US troops being sent to Uganda and neighbouring countries will probably remain there for "months," Vershbow said, emphasising that the Obama administration is not making "an open-ended commitment."
He added that a "small portion" of these troops will accompany African units to the frontlines.
"I don't anticipate they will get into the midst of combat, but I don't want to exclude that possibility," Vershbow told the committee.
The soldiers will carry small arms and other "self-protection" gear, he said.
The United States will not be using reconnaissance drones to track LRA movements, Vershbow added, noting that the most important type of intelligence in this instance will be that gathered "on the ground."
Yamamoto noted in addition that the US Agency for International Development is building mobile phone towers in the region to enable locals to supply timely information on LRA sightings.
In response to a question of whether armed drones might be used to strike the LRA, Vershbow said such an operational detail is "a delicate matter" best not discussed in a public forum.
The shadow of Vietnam crept over the Capitol Hill hearing room as Republican Congressman Don Manzullo said he fears that the number of US advisors may be expanded from 100 to 200 or 300.
Ted Galen Carpenter, a conservative analyst, made the reference explicit by noting recently, "The deployment of military advisors always entails the risk of escalation.
The extreme version of that process occurred in Vietnam with the initial dispatch of a few hundred advisors."
Obama's move to help Uganda and neighbouring countries finish off Joseph Kony's LRA was triggered by a law passed by Congress last year requiring the US to do more to end the terror scourge in central Africa.
The deployment of a small number of US advisors is in keeping with the arm's-length but lethal strategy Obama has employed successfully in Libya and in hitting targets in Somalia and Yemen.
Vershbow affirmed this approach by telling the House committee that the Africa mission is designed for "maximum operational impact while exposing US forces to limited risk."