Decades ago I subscripted/been a sponsor when assigned to Andrews AFB, but then they intended to put out an anti-American display [we bad] about our bombing Japan with the nukes that ended the war with Japan, and dropped my subscription, wrote a letter telling them as to why dropping them. So the have ben leaning left as far back as the late 70s.

Had to go to DuckDuckGo to find the info as all GOOGLE AI gave was about the 1995 one about the Enola Gay.

"In the late 1970s, the Smithsonian Institution planned a major exhibit on the atomic bombing of Hiroshima, which was later scaled back due to criticism from veterans groups. The final display featured a segment of the Enola Gay, the B-29 bomber that dropped the atomic bomb, along with a plaque and film about the mission."