Considering they had spaceships the size of football fields I think antagonizing them with a shotgun would have resulted in the aliens just landing on the farmhouse and squishing them all--THE END!
Second. The aliens are killed by water? So they land on a planet 3/4 covered with the stuff? They run around at night across lawns? What's on a lawn in the early morning? Dew? What's dew? Water?"
Consider the size of space. Consider that after being fought off with water, the aliens pack up and take off. Consider they didn't have suits to protect them from water. Obvious conclusion: This is a space-going race that needed food, so they stopped at the most likely local source, and NOT some invasion force heading to Earth particularly. That source was not going to be a perfect source of food, but they obviously nEEDED to grab people for food, and then when they were fought off they went away (the end implies the aliens were gone for good).
Consider that if the human race were to travel the stars and ran out of supplies, they couldn't simply turn around and go home--they'd have to go to the planet closest to them that had SOMEthing they could use for sustencance.
And seeing how any human could be killed by several inches of water in the bathtub, saying they wouldn't come here because water is deadly to them means we should all be packing and heading off, eh? No--like the aliens, we simply stay away from harmful contact with water.
"All the TV coverage is the Mexico situation? There's ships over DC and new York and CNN covers Mexico? The secret to killing them is discovered by the Arabs?"
Uh...yeah. I don't get your point--the secret to stopping them MUST be an American?
It was a silly movie.
Whatever, it was a SciFi Twilight Zone type movie--i.e. the science fictional elements were not there to explore such issues but as a set-up for a moral battle. Just as the Twilight Zone episodes were all about karma, this was about playing out the battle between belief and faith, coincidence and purpose. I don't think the director was trying to convince us that this is what a real alien would be like, he was using everything to add to his main point. And in this day and age, a scifi movie about faith in God isn't silly, not to me, at least.