Experts say a man accused of trying to sell a superbomb to al-Qaida made some incredible claims, but his estranged wife has no doubt that he had the ability to build an explosive. Before his arrest, Ronald Allen Grecula, 68, of Bangor, Pa., described an explosive of tremendous power to undercover agents who he thought were affiliated with the al-Qaida terrorist group, according to court documents. Grecula, who made an initial appearance Monday before a federal magistrate judge after his arrest Friday in Houston, told the agents he would sell them a bomb that could destroy everything within a half-mile...