"And that could be a logical conclusion from what's just happened," said North Korea expert Joel Wit at the 38 North monitoring group, run by Johns Hopkins University's School of Advanced International Studies.
The US military initially said in a statement dated April 10 that Admiral Harry Harris, the commander of Pacific Command, directed the Carl Vinson strike group "to sail north and report on station in the Western Pacific".
Defence Secretary Jim Mattis initially appeared to play down the deployment on April 11, saying the Vinson was "just on her way up there because that's where we thought it was most prudent to have her at this time".
But even Mattis initially misspoke about the strike group's itinerary, telling a news conference that the Vinson had pulled out of an exercise with Australia.
The Pentagon has since corrected the record, saying the ship's planned port visit to Fremantle, Australia, was cancelled - not the exercise with Australia's navy.
A US military official said the Vinson carried out the exercises after passing through the Sunda Strait and wrapped them up this week.