/abonnement/SPAIN – President Barack Obama arrived in Spain Saturday for an 18-hour stop, the first U.S. president to visit in 15 years, before returning home to pressing problems in his own country. White House officials said Obama is visiting Spain to demonstrate its importance as a NATO ally. With that in mind, the President will tour the U.S. Naval Station in Rota, Spain, where four U.S. Navy vessels are stationed to bolster NATO security. The President’s trip to Spain — likely his last to a European country as president — is highly anticipated by a nation that has not seen a U.S president visit since George W. Bush in June 2001 and whose political system is in chaos. (CNN)…[+]