All the cases you cite here, overweight, physical disabilities, etc., are conditions which make it very difficult to, for example, take part in combat. However, being trans-gendered is NOT a condition that prevents combat duty (there are already several thousand trans people serving honorably and effectively). Many trans service personnel have seen combat. Some are even Navy Seals (how tough is that?). If you are patriotic enough to enlist and if you can do the job, then you should be allowed to serve. Preventing Americans who are qualified to serve their country simply on the basis of sexual identity does indeed “violate fundamental constitutional and American values” - only a bigot would say otherwise.