No it isn't. See Thomas v. Lynch - 5th Circuit - August 7, 2015 - 14-60297. Thomas was born abroad, at a US Militray base. His father was a US citizen. Thomas is NOT a US Citizen.
This reading of the applicable laws, rendered in support of Loretta Lynch's DOJ, would have denied birthright citizenship to someone born in Kenya to a mother who did not qualify by age to pass on citizenship. Interesting!