And "Everyone has the right to life, liberty and the security of person." Military service also serves the purpose to defend that right when the country is attacked. Rights aren't absolute, they have to be traded off against each other.
Rights are morally absolute, and the cynical insistence that they must be traded off is both fallacious and intellectually hypocritical. You want certain weaker rights, then just admit it, don't be disingenuous about it.
Military service in the west is not for defence. Irak, Iran, Syria, Vietnam...