 Echoing Mr. Trump's call for national unity, President Biden making a brief address from the Oval Office last evening. We may disagree. We are not enemies. We're neighbors. We're friends, co-workers, citizens, and most importantly, we're fellow Americans. In the aftermath of the assassination attempt, there are many questions, and many of them focus on how the gunman, who was armed with a long rifle, was able to gain access to a rooftop so close to the scene of the Trump rally in Butler, Pennsylvania.