To understand the culture clash wracking the southern Philippines, consider the lechon. That's the name for the roast pig that's a Philippines' signature dish. Sold by the kilo in public markets, it's a must-have at any Filipino celebration. But pork is taboo for Muslims, now a majority in this city (about 60 percent, compared with 40 percent Christian), and who see this part of the southern Philippines island of Mindanao as their ancestral homeland. Eating pork is a no-no, and even smelling or seeing it is offensive to some. So what to do about the street lechon sellers? In Cotabato...