WASHINGTON -- Frustrated liberals are asking why a Democratic-controlled Congress and White House can't manage to close the Guantanamo prison or keep new gun-rights laws from passing. After all, President Barack Obama pledged to shut down the military detention center on Cuba for suspected terrorists. And Democratic control of the government would suggest that any gun legislation leads to tighter controls on weapons, not expanded use. Even as they grouse, however, liberal lawmakers acknowledge that no one factor explains last week's disappointing back-to-back votes in Congress. The Obama administration is focused on other priorities, they say. Party leaders don't want...