Actually, both Indian and HD won contracts to build a military sidecar with two-wheel traction, but the Department of War lost interest for it in favour of the Jeep.
The problem was that while Indian dedicated all his effort to the military vehicle, HD didn't forget their civil customers. Also, some changes in ownership led to the company being controlled by an englishman that was more interested in using the dealership network to introduce british bikes rather than to produce Indian bikes.
The Drifter is an amazing bike. As the former Indian models with valanced fenders, they are bikes you need time to get used to, you can either love them or hate them but nobody stays neutral. The difference is that the Drifter outperforms the new Indians in almost any aspect: electronic fuel injection, two sparks per cylinder, water cooling... It was discontinued in Spain after a couple of years, I reckon they sold less than 20. There is no nostalgic effect here as we never had the former Chiefs.
Raul