"I'm not very surprised (with Trump's absence) because the US government really has no clear agenda for the region", he said.
Peru's worldwide relations expert Miguel Rodriguez Mackay said Trump, who was expected to make his first visit to the region as USA president, has once again made his "contempt" for Latin America clear.
Since Trump has spoken to him twice since the chemical attack by the Assad regime to talk strategy, French President Emmanuel Macron will likely play a large role in the American government's response to the crisis.More news: Hamilton rues communication issues in Bahrain 'damage limitation' job
"The president will remain in the United States to oversee the American response to Syria and to monitor developments around the world", Sanders said in a statement.
Trump also faces domestic pressure, over an Federal Bureau of Investigation raid on the office of his attorney, Michael Cohen.
Trump has reportedly told White House officials that Vladimir Putin bore responsibility for the attack by backing Bashar al-Assad's regime, whereas Russian Federation denies that the poison gas attack took place at all despite videos and pictures shared on social media and news sites. Trump values his European allies and has often said so.
"I'm going to bet you he holds his regular schedule today", Kudlow said.More news: Kardashian boyfriend cheats in new video
Latin America analysts said they had expected to hear a national security-focused exploration of Trump's focus on border security and reducing illegal and legal immigration to the United States. He can work on his relationship with South America later, when he can stomach meeting its leaders.
In a statement, Pence communications director Jared Agren said: "The vice-president is honored to represent the United States at the eighth Summit of the Americas at President Trump's request".
Vice President Mike Pence will visit the summit on his behalf, but will not visit Colombia, according to EFE news agency. Chinese president Xi Jinping has made economic inroads in South America for years; the USA may try to reverse those gains and shore up economic solidarity against China.More news: 'We are sad and annoyed' - Jesus demands response from Manchester City