By Jonathan Allen (Reuters) – Ohio is set to enact a law that allows teachers and other staff to be armed with guns in schools once they have completed up to 24 hours of initial training. Proponents hope armed teachers will reduce the frequency and deadliness of school shootings, which have become recurrent in the United States. The bill’s opponents, including teachers’ unions and the state’s main police officer union, say it will only make schools more dangerous for children. The bill was finalized 10 days after a teenager with an AR-15-style rifle attacked a school in Uvalde, Texas. Nineteen…