Bolsonaro's much-hyped visit to Washington this week, which marked his first trip abroad for a bilateral meeting since taking office on January 1, was touted by officials as a new alliance between the two right-wing governments.

Following talks with Trump in the White House and a joint news conference in the Rose Garden on Tuesday, in which both leaders heaped praise on each other, a triumphant Bolsonaro tweeted that it was "mission accomplished."

"Important advances achieved in the economic, security and foreign policy areas, as well as the consolidation of the new path of a strong friendship between Brazil and the United States," Bolsonaro said on Twitter.

But a closer alignment with Washington could pose risks for Brazil as it struggles to recover from a record 2015-2016 recession.

Being a "priority ally" of Washington meant "buying the US security agenda: containment of China, hostility to Russia, hostility to Iran and permanent combat against Islamic fundamentalist terrorism," said Rubens Ricupero, a former Brazilian ambassador to Washington.

These "have little or nothing to do with the interests of Brazil" and could result in a "serious limitation of its foreign policy," Ricupero added.

As well as floating the idea of Brazil joining the NATO military alliance, Trump offered to support Brazil's candidacy to the OECD, a grouping of rich democracies, on the condition that it renounce its status of an emerging country in negotiations of the World Trade Organization (WTO).

Bolsonaro also agreed on technical safeguards to allow US commercial satellite launches from Brazil's Alcantara base.

Political analyst Matias Spektor tweeted it was the "biggest package of concessions" given by a US president to a Brazilian leader in the past 30 years.

But Ricupero warned the waiver of differentiated treatment in the WTO would be "a disaster, because it would have very negative effects in terms of tariffs and would alienate Brazil from the developing countries with which we have always conducted a common policy."

- Lopsided relationship -

The Trump-Bolsonaro bonding matters for the United States, which has had strained relations with Brazil's long string of leftist governments.

As Latin America's biggest country, Brazil has a major role in the US-led campaign to pressure Venezuela's hard-left President Nicolas Maduro from power and in resisting growing economic influence across the region by China -- which is Brazil's main trading partner and represented 27.8 percent of its exports in 2018.

But Brazil could find itself in a lopsided relationship after making concessions and only getting "some promises," said David Fleischer, a political science professor at the University of Brasilia.

The American academic said these promises "will probably not be fulfilled, because Washington has a very independent foreign policy," defined by Trump as "America first."

Fleischer's skepticism was shared by many Brazilian Twitter users, who have flooded the social media site with accusations that Bolsonaro had shamed Brazil by acting like a US "puppet".

Bolsonaro's supporters, however, hailed the leader's US trip as a "great day" that would make Brazil stronger.