For Liberty and Glory (James R. Gaines, 2007) is a joint history of the American and French Revolutions, viewed through the lens of Washington, Lafayette, and their friendship. Though I know quite a bit about both revolutions, Gaines highlights linkages between the two beyond the obvious and brings the social and cultural context forward more than most histories of the era.
Gaines doesn't explicitly say so, but reading his account of events in France made me wonder if the difference in population density impacted the outcomes almost as much as the fact the Americans had some experience of self-government and came from a system that already limited the powers of the monarchy, while the French were trying to move all the way out of absolutism at once. America, a country with low population density and no city close to the size of Paris, could handle the chaos of a revolution and the weak central government prior to the Constitutional Convention because such uprisings as there were were isolated, and they didn't have a big, half-starved city providing angry mobs to drive the revolution to unhealthy extremes.
Before reading this book, I didn't know much about Lafayette, but I ended it admiring him. He wasn't the most brilliant figure of his age, militarily or politically, but he was honorable, courageous, and consistent--he had his principles at 19, and he followed them still at 70. And I have to admit to getting a bit verklempt at the end, when Gaines points out just how much of Lafayette is in the Constitution of the Fifth French Republic--i.e. the current one, the one that gives every appearance of being here to stay. That's the vindication of history for you.