Trump — who highlighted fears about an asylum-seeking caravan of migrants heading to the southern border as he campaigned for Republican Senate candidates in 2018 — on Monday referred to a “Humanitarian and National Security crisis on our Southern Border,” and Vice President Mike Pence told reporters the same day that the president was considering declaring a national emergency over the issue.

While there is some agreement about humanitarian concerns for traveling and detained migrants, particularly the children who have been separated from their families, there’s dispute about whether there is a security crisis at the border. While it’s true that there were more arrests at the border in fiscal year 2018 (396,579) than in fiscal year 2017 (303,916), according to U.S. Customs and Border Protection data, the 2018 figure is less than the average over the previous decade.

Amid the heated debate in Washington, the issue of whether or not there’s an immigration crisis has polarized the voting public.

Seventy-two percent of Republicans said there’s a crisis of illegal immigration, more than three times the share of Democrats (19 percent) who agreed. But Democrats are not writing off the issue entirely: More than half (52 percent) said there is a problem with illegal immigration across the U.S.-Mexico border.