South America’s migration toward conservatism is expected to gain momentum Sunday when Chileans vote for president. The choice is stark: a lifelong member of Chile’s Communist Party or two rightwing candidates.

The Communist, Jeannette Jara, is expected to come in first. But one of the two conservatives, each a Donald Trump fan, is expected to win a runoff on December 14. Rising crime, a surge in immigrants, and violence by Venezuelan gangs are pushing voters to the right. Vowing to ‘Make Chile Great Again,’ Republican Party candidate  José Antonio Kast promises to expel all undocumented migrants and to build a 15-feet high “Border Shield”  along Chile’s nearly 700 miles of border with Bolivia and Peru.

Outflanking him on the right, another German-Chilean, Johannes Kaiser, candidate of the new National Libertarian Party, has said that if crime and illegal immigration are not brought under control he would favor a repeat of the military coup that brought Army General Augusto Pinochet to power in 1973. In a December 14 runoff, polls indicate that either rightist would easily beat Ms. Jara, a 51-year-old former Labor minister who joined the Communist Party at age 14.

Disillusioned with their three-year-old ‘democratic socialist’ government, Chileans are following a trend seen elsewhere on the continent, notably in Bolivia, Argentina, and Venezuela. In Ecuador, a conservative businessman, Daniel Noboa, was elected president two years ago. Next spring, rightwing candidates may win the presidencies of Colombia and Peru.

Last Saturday, in Bolivia, Christian Democrat Rodrigo Paz Pereira was inaugurated president Saturday, ending two decades of rule by the leftwing Movement For Socialism, or MAS. Leftist rule was so disastrous that MAS lost all but two seats in Bolivia’s Congress in the general election last August. Mr. Paz, a graduate of American University in Washington, promises to restore relations with the United States and Israel and to cancel lithium mining deals with China and Russia. 

Secretary of State Marco Rubio congratulated Mr. Paz, saying that his victory marks the end of nearly two decades of “government mismanagement and bad governance in Bolivia.” After campaigning on the slogan “Capitalism for All,” Mr. Paz plans to promote small business and small government, emulating Javier Milei, president of neighboring Argentina.

Two weeks ago, Mr. Milei, a self-described “anarcho-capitalist” decisively beat Argentina’s left wing Peronists to win a near majority of seats in Argentina’s Congress. Helping his ‘Freedom Advances’ party was lowered inflation. The  annual rate fell to 32 percent in October, down from 289 percent near the start of his term, 18 months ago. Equally important, two weeks before the election, President Trump  put his finger on the scales by offering Argentina up to $40 billion in government aid and private investment.

“If he wins we’re staying with him, and if he doesn’t win, we’re gone,” Mr. Trump said after hosting Milei at the White House last month. After the vote, Mr. Trump, posted on Truth Social “Congratulations to President Javier Milei on his Landslide Victory in Argentina.” He added: “He is doing a wonderful job! Our confidence in him was justified by the People of Argentina.” 

American billionaire investor Bill Ackman posted on X: “An important win for democracy, capitalism, and sanity, and a defeat for socialism. NYC take notice.”

In Buenos Aires, the Argentine leader told his supporters: “I am king of a lost world.”  He referred to the country’s golden age — prior to 1929 — when the country ranked among the 10 nations with the highest per capita incomes in the world. Mr. Milei said: “Today we have passed the turning point. Today we begin the construction of a great Argentina.”

Yesterday, the White House announced that the US and Argentina reached a deal to deepen “bilateral trade and investment cooperation.” In a market opening move,  the White House said Argentina will provide “preferential markets access for US goods exports.”

At the northern end of South America, in Venezuela, Mr. Trump is engaging in gunboat diplomacy. The world’s largest warship, the USS Gerald Ford is moving toward Venezuela at the head of the largest assemblage of US Navy warships in the Caribbean since the Cuban Missile Crisis of 1962. The goal appears to be to pressure President Nicolás Maduro to step down and flee the country. A quarter century of leftwing rule by Mr. Maduro and his predecessor Hugo Chávez has beggared Venezuela, once the richest country of South America. 

Production of oil, the country’s main export, was 950,000 barrels a day last year, about one third the level of 2002, when the leftwing governments started. In the 12 years since Mr. Maduro took over, 8 million Venezuelans, or one quarter of the population, have emigrated. Analysts say that to keep power, Mr. Maduro stole last year’s presidential election. He ignored voter station tally sheets that indicated that the opposition candidate won about 60 percent of the vote. 

Last month, opposition leader María Cortina Machado was awarded the Nobel Peace Prize. She dedicated her prize to “President Trump for his decisive support of our cause.” A conservative businesswoman, Ms. Machado has vowed to “bury socialism forever.”

Regime change in Venezuela could help the next leader of Chile. Repatriation of undocumented Venezuelans is increasingly a goal of conservative politicians. Since 2017, the number of Venezuelans living in Chile increased 12-fold, to 670,000 last year. According to a poll by Activa Research, 85 percent of Chileans feel ‘socially distanced’ from Venezuelans. 

Mr. Kast, the rightist, promises in a political ad: “Chile has been invaded…but this is over.” Citing the Trump Administration  as a model for Chile, he claimed last month that this year, the United States has deported 500,000 migrants, prompting another 1.6 million to ‘self-deport.’

Rightly or wrongly, immigrants are blamed for a surge in crime in Chile, traditionally a low crime nation. In this nation of 20 million people, almost 30 percent of people were victims of some type of crime last year and almost 40 percent of homes were attacked, official data indicates. 

Over the last decade, the private security sector has tripled in size, according to a study by the National Chamber of Commerce. Now candidate Kast vows:  “We are going to recover order, security, power and the authority of the State.”