Members of the European Union (EU) are feeling besieged by a rising tide of refugees fleeing conflict and migrants seeking economic opportunity. Many of the refugees, who are mainly from the Middle East and Africa, are crossing the Mediterranean on overloaded boats or traveling via treacherous land routes, often victimized by unscrupulous human traffickers. National leaders disagree on what to do, other than fortify Europe's borders. Refugee organizations say strengthened borders will just push migrants, who have been dying by the thousands, to try even more dangerous routes. An EU plan to send navies to destroy smugglers’ boats faces similar criticism. Some economists argue that Europe needs more migrants to bolster its aging workforce. However, polls show most Europeans want fewer immigrants amid worries about unemployment and terrorism. Violent conflicts far from Europe — primarily the Syrian civil war — are driving this year's surge. That leads some observers to argue that an international solution to the migration crisis is needed.