The following is based on new findings from two consecutive University of Maryland Critical Issues Polls, conducted September 3-20, and October 4-10. The full results can be found here, and the methodology and questionnaire here.
From the day President Trump announced his decision to withdraw troops from northern Syria, which we started measuring on October 7, support for his move was low, with only 27% of respondents saying they supported it (including fewer than half of Republicans). Within two days, as criticism mounted against the decision, including by GOP Senators such as Lindsey Graham, support for the decision declined further to 21%, and opposition increased from 42% to 46%. At the same time, it is notable that, overall, fewer than half of respondents opposed the move outright by the time we closed the poll on October 10, which was prior to the overwhelming bipartisan vote in the House of Representatives to oppose the Syria withdrawal.