Looking for “Deep Dive” but short books on the history/culture/evolution of India, Russia, and the US?

I’m looking for book suggestions to understand the 'soul' and evolution of three specific countries: India, Russia, and the USA. I’m a PhD student, so I appreciate high-quality research and 'content-heavy' writing, but I’m looking for books that aren't 800-page doorstops. I want titles I can finish relatively quickly that still offer a profound understanding [...]