In The Kite Runner, how was Baba different in the U.S. than in Afghanistan?

Baba was a powerful man in Kabul and one of the wealthiest
in the city. Financially successful, he lived in a fine home, employed many servants,
and threw fancey parties for his influential friends. Even while living in Afghanistan,
he always had a love for things American, driving a Mustang and wearing fashionable
Western clothing. He always considered America the most powerful nation in the world,
and his respect for it led him there following the Russian takeover of his country. But
he left Kabul penniless, and upon arrival in California, he found himself to be just
another immigrant in a nation of transplants. He found himself working in a gas station,
driving an old van, and living in a small apartment. Only among the small Afghan
population around San Jose did he find the respect that he had known in his native land.
His confidence lost, Baba settled into a life of lower middle-class existence, focusing
on the education and maturation of his son. Once a bear of a man, lung cancer took over
his body, reducing him to a shell of his old physique. But his relationship with Amir
thrived during his life in California, and watching Amir grow into a mature
adult--successful in school and in love--allowed Baba to die a happy
man.