This has me stumped, my other great grandfather, I always known him as Lee May but census records shows him as Leander also. He was born 26 Jun 1881 Magoffin County, Kentucky and died 21 Jan 1953. I was always told his was in the Spanish American War. I would think he would be too young though and maybe he was in WWI instead. I have never been able to find anything other than having a photo of him in uniform. http://www.findagrave.com/cgi-bin/fg.cgi?page=gr&GSln=may&GSfn=leander&GSbyrel=all&GSdyrel=all&GSst=19&GScntry=4&GSob=n&GRid=10931203&df=all&
The Spanish-American War seems more likely than WWI. His marker has his birth date as 20 June 1880. He would have been 18 in 1898, and 38 in 1918. As with Adam Marshall, I would suggest trying to request his service records from the National Archives. The down side is that it may take up to a year to get anything from them. If you don't mind spending some money, you could hire a researcher. It's not free, but it will take a fraction of the time compared with the NARA.