When India's Prime Minister Narendra Modi concludes his three-day visit to Washington on Wednesday, he will likely reflect on how the relationship between the world's two biggest democracies is becoming ever closer, a step towards fulfilling US President Barack Obama's prophesy that India and the United States would form "one of the defining partnerships" of the 21st century.

At the very least, Modi deserves credit for generating an impressive amount of air miles. This week marks his fourth U.S. visit since assuming office in 2014. It is also the seventh time he has met Obama.But there is an important first this week too: Wednesday will mark the first time Modi has been invited to address a Joint Meeting of Congress in the House Chamber -- an honor bestowed on just a few world leaders every year.

Wednesday's address to Congress will complete an unlikely turnaround for Modi, going from outcast to prize in just over two years.  Read more