Actually most of the shti you get grown in north america aint strains from afghanistan. Strains from climates like that are sativa, they grow tall and lanky. For a good indoor grow you want indica, which is shorter and bushy.
Pure indicas can flower in little as 40 days, so no wonder the commercial drug dealers use indica dominant strains.
But sativas can provide different highs. More psychedelic highs, but most pure sativas require 130 days to flower indoors and they'll flower into october ourdoors in the n. hemisphere lol. There are sativa dominant strains out there but commercial growers wouldn't grow them unless it was for personal use.
Most of the 'elite' stuff out there are actually prized clone variations. Easy to keep weed plants alive forever if you keep them in 18 hour light cycles.
Actually, the indicas used in America are afghani. The skunk, northern lights hybrids were all indica domiant from afghanistan originally. They grow indicas overthere. Sativas grow in tropical climates, or climates of high elevation with extreme sunlight. The best indicas grow in highlands of pakistan and afghanistan.