"He (Modi) has, in a sense, sent a message that no matter what he thinks about the US, he definitely wants to take the relationship in a new direction. I think that's really the critical point that the invitation symbolises," Ashley Tellis of the Carnegie Endowment for International Peace, said.
Modi, he argued, has used the invitation as a way of signalling that the United States really looms large in his calculations for where he wants to take India.
"I think this is an important point because we all know that Modi has had a difficult personal history with the US and there was quite some uncertainty about how he would view the country when he comes into office.
"It (the rare invitation) was entirely because Modi left Washington with a very, very good feeling about President Obama. I mean he came here really uncertain about what kind of reception he would receive because of the history of his troubles with the US," Tellis said.
"New York was a triumph for Modi. I mean he was superstar. But Washington was equally a triumph. Even though there
"They had a lot of private time at dinner and the next morning they had an extended one on one, which again, much to his surprise went off much better than he had hoped. The walk to Martin Luther King memorial really touched him," he said.
Modi hasn't been in office yet for a full year but he already is demonstrating kind of a willingness to break some of those older truisms to have equal ties with all great powers, focusing multi-alignment, Alyssa Ayres of the Council for Foreign Relations, said.
"Modi doesn't have any of the hang-ups that previous predecessors might have had about what will it mean if he appears too close, or appears to be leaning too far in the direction of the US. He just simply doesn't care," she said.
When Obama lands in New Delhi this time, he will discover a political landscape changed dramatically since Modi's sweeping electoral victory last May, president of the Center for a New American Security, Richard Fontaine said.
"Coming just four months after Modi's visit to the US, Obama's trip will be long on symbolism and vision," he said.
"The election last May of Prime Minister Narendra Modi has injected new enthusiasm about the sometimes difficult relationship in both New Delhi and Washington," said Sadanand Dhume of the American Enterprise Institute.