However, being able to “bring those sons of bitches down” depends entirely on the larger craft having their primary weapon engaged. Again, these ships were truly enormous, and we saw that even when one had been brought crashing to Earth, it was still roughly 50 per cent intact, which means it’s not unreasonable to think that a distress call would have been made warning other alien ships that their shields were down, ship-wide systems seemed to be malfunctioning and all contact with the orbiting mother ship had been lost. Plus, of course, a warning about engaging their primary weapon.

So, would all 15 spacecraft have been destroyed? Without one single ship plotting an emergency evasive course to get the hell out of Earth’s atmosphere? Which then leads to the potential of calling reinforcements. A nice plot element to consider for the sequel. Or, how about another race – that had also previously been savaged – contacting Earth after the attack to join forces? Another potential story line.

But we have so much still to consider. If a sequel were set within the lifespan of the principal characters, we would have to see the state of the Earth after the attack.

Almost all of the major cities around the world have been destroyed. How long would it take to rebuild New York, or London or Los Angeles or Tokyo? A long time. Would they be rebuilt in the same way, or totally different? Society as a whole would have changed completely as well. We now know, beyond any doubt, that we are not alone in the universe. What are the religious implications?

We also now know that there are extremely hostile forces in the universe and we must rebuild with an aim to be able to defend our fragile little planet.