New Delhi (CNN) Donald Trump heads to Houston, Texas, on Sunday to join a major rally of tens of thousands of Indian-Americans, but the US President won't be headlining.

Instead, Indian Prime Minister Narendra Modi will be the star.

"Howdy, Modi!" is billed to be the largest gathering for any foreign leader visiting the US, "other than the Pope," according to the event's website.

As a fan of impressive crowd sizes, it's the type of hyperbole you can imagine Trump appreciating.

And, in more ways than one, Trump and Modi are cut from the same cloth.

Both populist leaders energize their respective bases with big rallies and even bigger personalities. They've received criticism at home for driving wedges through their electorates along religious and cultural lines. And their particular brand of "Made in America/India," have meted mixed results.

Their similar strongman tactics have also landed them at loggerheads. After failing to secure a trade deal earlier this year, the leaders have exchanged tariffs. But the joint appearance Sunday seems to indicate there's no love lost.

Make India Great Again

Over the last five years, Modi has consistently trumpeted the slogan that would become Trump's signature campaign promise: India (or America, in Trump's case) comes first.

Within months of taking office in 2014, Modi launched "Make in India" -- a campaign promoting local manufacturing.

His goal? Building a self-sufficient economy capable of feeding a population of 1.3 billion.

Now, as India's economy stagnates, that message is faltering -- an obstacle Trump has not yet had to face down.

In 2016, Modi's government demonetized 85% of the country's currency and plunged the economy into chaos. And in 2017, the government enforced a goods and services tax, which has since been repeatedly amended to counter widespread objections. Last month, they pushed a constitutional amendment through Parliament that downgraded the federal status of India's only Muslim majority state -- Jammu and Kashmir.

India's economy slowed to a 6-year low, expanding just 5% in the April-June quarter, with analysts warning the slump could persist for the next few years. The country's unemployment rate is also the highest in 45 years and the manufacturing sector is heading into a recession.

Hopes that Modi's ambitious economic programs for India -- Asia's third largest economy -- would lead to massive growth are dwindling.

"If you are a lower middle-income economy (like India) then it is important to sustain growth. And it should be able to sustain growth for years while for developed economies these kinds of cycles are quite common," said Suyash Rai, a fellow at Carnegie India, a think tank.

Controversial outsiders

In the run-up to the 2014 national elections, Modi introduced himself as a political outsider -- much like Trump.

He sold himself as a former tea seller with a tough reputation, a great administrator and India's only hope against a dynastic political party that had run its course.

His popularity has only increased since then. Modi and his right-wing Hindu nationalist Bharatiya Janata Party (BJP) won re-election this year with an even bigger mandate than the last time, even amid criticism about their track record on human rights.

During a campaign rally this year, Modi's chief aide and now India's Home Minister, Amit Shah likened migrants from Muslim-majority Bangladesh as "termites" and promised to throw them out of the country.

The past five years in India have been marked by an increase in tensions between Hindu-Muslim communities, widespread mob lynchings, and nationwide protests by India's lower-caste Dalit community.

Last month, in an exercise to weed out illegal immigration in the eastern state of Assam, the government excluded 1.9 million Indians from the National Register of Citizens, who now stand to lose statehood if they're unable to win a labyrinthine appeal process.

Modi-Trump bromance?

India and the US have gradually become natural allies over the past few decades as they arm themselves against China and growing destabilization in the South Asia region.

Since Trump took office, both leaders have met a number of times.

"It means that at the highest level there is clear intent to find common ground and make this bilateral relationship work across various domains from trade to defense to diplomatic relations," Rai said.

This latest high-profile meeting in Houston comes after months of escalating tensions between India and the US over trade.

Trump has repeatedly slammed India for taking advantage of the US, and both countries have slapped fresh tariffs on each other over the last year.

India's move to impose tariffs on 28 US products, including almonds, apples and some chemicals came into effect weeks after Modi won re-election.

But analysts are finally expecting positive movement at Sunday's event after a year of friction over trade.

"Reports suggest that they have been intensely negotiating and talking about finding common ground on those issues. There could be an announcement," said Rai.