For Belfast, Keeping Peace Means a City of Walls When President Obama comes to Belfast, he's expected to praise a country at peace and call for walls that separate Irish Catholics and British Protestants to come tumbling down. Barely a 10-minute walk from where the U.S. leader is speaking Monday, those walls have kept growing in size and number throughout two decades of slow-blooming peace. Residents today on both sides of so-called "peace lines" - barricades of brick, steel and barbed wire that divide neighborhoods, roads and even one Belfast playground - insist the physical divisions must stay to keep violence at bay. Belfast's first peace lines took shape in the opening salvos of Northern Ireland's conflict in 1969, when impoverished parts of the city suffered an explosion of sectarian mayhem and most Catholics living in chiefly Protestant areas were forced to flee. The British Army, deployed as peacekeepers, erected the first makeshift barricades and naively predicted the barriers would be taken down in months. Instead, the soldiers' role supporting the mostly Protestant police soon inspired the rise of a ruthless new outlawed group, the Provisional Irish Republican Army, committed to forcing Northern Ireland out of the United Kingdom and into the Republic of Ireland. For all the unlikely triumphs of Northern Ireland diplomacy since the U.S.-brokered 1998 Good Friday peace deal - a Catholic-Protestant government, troop withdrawals, police reform, and disarmament of the IRA and outlawed Protestant groups responsible for most of the 3,700 death toll - tearing down Belfast's nearly 100 "peace lines" still seems too dangerous a step to take. I'd love to see that wall taken down and I could say hi to my neighbors, but it isn't going to happen. There'd be cold-blooded murder and I'd have to move out," said Donna Turley, 48, smoking a cigarette at her patio table in the Short Strand, the sole Irish Catholic enclave in otherwise Protestant east Belfast. Right behind Turley's backyard refuge towers a 50-foot (15-meter) wall. It starts as brick, transitions into fences of corrugated iron, and is topped by more steel mesh fence. Each layer marks the history of communal riots like the growth rings of a tree. Higher still, two batteries of rotating police surveillance cameras monitor Turley and her Catholic neighbors, as well as the Protestant strangers living, audibly but invisibly, on the far side. It's terrible looking. But I wouldn't feel safe if it wasn't there. I couldn't imagine that wall being torn down. Nobody here can," said Tammy Currie, 21, who is Turley's nearest Protestant neighbor, standing in her own small cement patio backed by the wall. Her 3-year-old son jumps on a trampoline that a few months ago had to be cleared of shattered beer bottles thrown from the other side. Both families rent state-subsidized homes provided by the Northern Ireland Housing Executive, which is responsible for making their homes as safe as possible from the risk of further rioting. That means both have triple-layered Perspex windows that are foggy-looking and unbreakable, and metal-tiled roofs that can't be set on fire.