The part I find appalling is that, after two men opened fire on a Philadelphia bus, aiming at the passengers within, their defense is that they should not be charged with assault because no one was injured.
What a fascinating legal principle: "No harm, no foul."
Except that's not how our legal system works. We have a little thing called the Common Law system, based on hundreds of years of precedents, mostly from England. How did that happen? A series of what are known as "reception statutes" were enacted in post-Revolution America. Some were legislative acts, some were court decisions, the rest were written into state constitutions. Here, for example, is the New York one, enacted in 1777:
[S]uch parts of the common law of England, and of the statute law of England and Great Britain, and of the acts of the legislature of the colony of New York, as together did form the law of the said colony on the 19th day of April, in the year of our Lord one thousand seven hundred and seventy-five, shall be and continue the law of this State, subject to such alterations and provisions as the legislature of this State shall, from time to time, make concerning the same.
By adopting English common law, with the right to make changes as needed, the new states avoided the legislative nightmare of having to create an entirely new legal system. Given that the colonies the states derived from had also followed English common law, this meant they could keep their courts and legal systems as they were. It was a practical decision, but also an ideological one; the newly independent states may no longer be subject to the British crown, but they still saw themselves as culturally and philosophically British. And so, throughout the United States of America today, we still follow the British common law legal system. Oddly enough, the words "no harm, no foul" are not found in that system. Nor has such a clause been added by any American state. Instead there is a legal definition of the term "assault" that goes something like this:
an intentional act by one person that creates an apprehension in another of an imminent harmful or offensive contact
The key elements here are intent and apprehension of harm. The video shows a bunch of very scared people running and ducking, and in one case crawling under a seat. That pretty much covers apprehension. As for intent, aiming a gun at someone and pulling the trigger satisfies that condition.
There has been a great deal of abuse of the rule of law in the U.S. in recent years, most notably in areas where massive harm has gone unpunished. Notions like "too big to fail" and the need for restitution does outweigh the need for prison corrupt our justice system. They replace the notion of justice with harm minimization, a dubious concept in principle and even more dubious in execution. But creating new definitions of criminal acts based on wishful thinking is not yet the common law for the common people, only the super-rich.