It's funny that this guy is citing a Constitutional Amendment when the Constitution nowhere even enumerates the privilege of government-subsidized athletic programs, let alone a standing army. Consider this for a moment: there are individuals across the United States who are actively and systematically being forced or coerced to surrender a fraction of the product of their labor in order to afford US-born and naturalized citizens alike the life of a professional athlete. There exists nothing within the Constitution, the Bill of Rights or the ensuing Amendments which authorizes such a military unit.
By the way, the 14th Amendment was a post-bellum power-play by the central government in an effort to expand its influence under the guise of political righteousness. The 14th Amendment forever altered the sovereignty of individual states and persons, capitalizing on the post-war flavor of nationalism. It effectively and expediently systematized the targeted antagonist of the 13th Amendment into softer, more intellectually-palatable and ubiquitously-applicable forms, never to absolutely abolish it but rather to expand its reach.
This is the ironic consequence of political borders: they forestall the advances and fruits of globalization, which tend to organically acquaint persons across the world, of varying characteristics and interests, and with diverse dispositions. Of course, these many flags and territorial jurisdictions fail to uniquely encapsulate the athletes who ultimately sport their respective nations' colors; however, people inherently become passionate in competition, gravitating to rallying cries such as "Remember the Alamo" or "Detroit vs Everybody" which are wildly emotional and popular yet largely indecipherable.