Ms. Miller, who wrote under the name “Private Second Class Citizen” about enduring gay slurs and faking a heterosexual dating history, is transferring to Yale University this fall and has become something of a media celebrity, appearing on “The Rachel Maddow Show” on MSNBC and on ABC News.

Interviews with three gay cadets, who spoke on the condition of anonymity because revealing their identities could result in expulsion, as well as conversations with Ms. Miller and several gay alumni, painted a portrait of a vibrant, if tiny, gay underground at West Point. The hiding begins on Day 1: new cadets must sign a document acknowledging that revealing one’s homosexuality can lead to discharge, as can demonstrating “a propensity to engage in homosexual acts.”

In 1996, three female cadets resigned after West Point officials found a diary belonging to one of them that revealed their sexual orientation. In 2002, the academy discharged a cadet after his profile was discovered on a gay Web site. Ms. Miller, whose blog began in April but apparently eluded academy officials, said she quit voluntarily by submitting a letter revealing her lesbianism.

Asked about gay culture at West Point, Lt. Col. Brian Tribus, the academy’s director of public affairs, issued a statement saying that the school “will continue to apply the law as it is obligated to do,” but also noting that cadets must take military ethics classes that include “topics about unconditional positive respect for others.”

For gay cadets, repressing their sexuality is just one part of adapting to West Point, where life is regimented and lived mostly in uniform. Romance of any kind can be difficult: the 4,400 cadets, who live in one complex of large barracks and eat together at huge weekday breakfasts and lunches in Washington Hall, are allowed to date but not to kiss or hold hands while in uniform. “It’s like living in a snow globe,” said one lesbian cadet, who is in her third year.