If they don't, billions of dollars could be a stake.
When Modi meets Trump on Monday at the White House for the first time, a big elephant will be in the room: immigration and the hotly contested H-1B program.
India continues to be a big beneficiary of this popular visa program, a key way Indian IT talent makes its way to the U.S. to work for Silicon Valley's biggest companies, such as Apple, Google and Accenture, among others.
But over the past three months, Trump unveiled the "hire American buy American" initiative, which has put the current H-1B program under review. Any dramatic changes could hurt India's IT outsourcing industry, which plays a significant role in driving India's economic growth.
A senior Indian government official said Modi is prepared to dive into this complicated discussion by highlighting the value Indian-Americans have contributed to the U.S. economy, including an estimated 64,000 jobs.
Modi may also use Indian IT firm Infosys as a poster child for investment from the outsourcing industry. Infosys recently announced it's planning to hire 10,000 Americans over the next two years to demonstrate a willingness to invest in U.S. jobs.
Defense is also a topic where both leaders share similar goals.
Modi will likely communicate India's strong desire to buy more U.S. arms, which may appease Trump's interest in increasing U.S. exports.
Modi is specifically interested in high-tech drones from General Atomics to better patrol the Indian Ocean. This would likely have a large price tag and would require the approval of Congress.
"Defense is where India and the U.S. will likely see eye to eye," IHS Markit's Vice Chairman Daniel Yergin, an energy and international politics specialist, told CNBC.
Monday's meeting will likely be more about relationship building than dealmaking.
After all, the leaders of the world's two largest democracies have a lot in common.
Both are considered strong, nationalist pro-business leaders that benefited from the wave of populism that allowed them to hone in on the frustration many citizens were feeling.
Modi and Trump also seem to believe in the power of social media. Modi is the second-most-followed global leader on Twitter, with over 30 million followers, second to Trump's almost 33 million followers.
Modi also was looking outside of social media for ways to use technology to connect with people.
During a community reception hosted by Indian Ambassador Navtej Sarna on Sunday afternoon in Virgina, Modi spoke to a packed house of Indian-Americans, many of whom traveled from across the nation to meet him.
He encouraged them to download the "NarendraModi" app.
According to its Google Play description, the app offers "instant" updates of information and the ability to contribute to tasks as well as longer messages from Modi.
Correction: This version corrected the first name of Daniel Yergin.