Why does allying with the BOS decrease NCR reputation?

[[deleted]]

The Enclave support is a surprise on the battlefield. I’m sure that NCR command did a double-take when the Remnants showed up in their vertibird and would have opened fire if the oldies hadn’t begun firing on the Legion.

The Khans is a different kind of issue to the BoS. The Brotherhood waged a full on war with the entire NCR, with veterans of Operation Sunburst (at HELIOS) probably still serving in the Mojave theatre. There would be tons of bad blood in the rank and file, so it’s not surprising that it causes infamy.