That being said, the movie offered surprisingly spineful allegory to our contemporary struggle against the "religion of peace." Some allusions I've drawn with movie parts in italics and my take following (if you're planning to see the movie but have not yet, then you may not want to read on):
The consternated city dwellers are taken completely by surprise when the killer tripods bust out of the ground. No one saw it coming, yet it is revealed to us later in the movie that these vehicles of destruction have been in place for millions of years.
Well, Islam and Salafism are only a millenia-and-a-half old, but for practical purposes they've been around forever, sitting in the ground, awaiting a warm body to use them for the purposes of destruction. Wahhabism, the particularly dangerous element within Islam, has also existed for centuries. The recent history of terrorist attacks by Muslim extremists is not something that sprung out of the blue on 9-11. They date at least as far as the 1988 bombing of PanAm flight 103. Yet everyone was blithely unaware.
Some, like the auto mechanic who gets vaporized after fixing Cruise's getaway vehicle, remain oblivious even after the major attacks have started. He actually goes after Cruise for overreacting to the threat.
There exists plenty of people who downplay the threat posed by Islamic terrorism, some claiming the West deserves what it gets, and other quixotic dunderheads patently deny that any such threat exists at all. Private groups (ACLU, Amnesty International, etc), academia, and the media form the axis of such beliefs. Until a dirty bomb rips their homes apart, their opinions are not going to change.
Constant bickering between Cruise and his two kids threaten their collective survival on several occasions.
A house divided inevitably falls. Predictably, less than a day after the London bombings, partisans were making vicious attacks on Bush and Blair foreign policiy as these leaders were essentially blamed for the bombings. I, like most people, have plenty of concerns with our foreign and domestic policies. But family members screaming at one another while the reaper closes in does no one any good.
Cruise's son is the first character to become visibly angry at the alien destroyers. Surveying the damage around his father's house, his gritted teeth make clear that he doesn't want to run and hide; he wants to exact revenge. The terror-struck daughter is too shocked to display any emotion but fear. Cruise, the one putatively in charge, is notably the most ambiguous in his reaction.
Public sentiment on Islamo-fascist terrorism: Some people panic, some want to hide, some are indifferent, and some want to strike back. Meanwhile, the one's on top try to triangulate everything to please everyone, and consequently have little personal conviction. Bush takes a hard-line in Afghanistan and the Middle East, but leaves our borders ripe for breach. He talks about winning hearts and minds by understanding Middle Eastern culture, yet we bend-over backward to avoid offending rabid animals by treating them like royalty even while they're imprisoned, ignoring a fundamental aspect of Asia Minor's culture: never compromise.
While driving the acquired vehicle through a city on their way to Boston, Cruise and company are surrounded by the rabble wishing to hitch a ride. As they insult and attack Cruise for what he is doing, he tells his kids "they're only envious." Cruise's crew is ousted, and another driver takes over. He is subsequently attacked in a way like Cruise and then he is shot and killed.
Hard-liners are in the van, and the critics (read Western Europe) are mauling it as it drives along. Criticism of US policy's lack of concern for human rights, especially those regarding the treatment of detainees in places like Gitmo, comes from places that have policies that are often harsher than those in the US when it comes to dealing with potential enemies of the state. In France, for example, as many as 70% of the prison population is Muslim, even though Muslims make up around 10% of the French population (this is proportionately much more imbalanced than that of black vs white prison rates in the US--in other words, Muslims pose an order of magnitude more danger in France than blacks do here in the US). In the Netherlands, talk of ending Middle Eastern immigration altogether is in the air. Those who are in the position to respond to the threat Islam poses (ie countries that have militaries, like the US, GB, and Australia) are rabidly criticized by others who are similarly threatened but lack the means to do anything about it (western powers who have no military might or backbone, like France and Germany).
When Cruise and his daughter take shelter with the eccentric Tim Robbins character, Robbins notes that history tells us no occupying army can ever win.
US boots on the ground in the Middle East are not going to transform the place into a haven for the US. It's too costly to stay, the soldiers become easy targets for terrorists, and enemies of the West become galvanized by people on their home turf. Robbins believes that the aliens are making a fatal mistake if they try to hang around on earth with humans still living, because it will unite humanity in its will to resist, and it will drain resources from the aliens. Also, the aliens are essentially leveling the playing field when they should be utilizing an enormous technological advantage (why are we fighting street-to-street urban warfare when the air force could incinerate the insurgent hotbeds without losing a soldier?).
Robbins wants to go underground, to fight the aliens in secret.
I understand his sentiment. But I suppose Spielberg's message is that it is foolish for the US to alter its principles to combat terrorism. That is, no clandestine torturing, dealing with monsters (like most of the House of Sa'ud), or targeting civilians. I hope we don't have to resort to such extremes, but interestingly after Cruise takes Robbins out, he basically does exactly what Robbins was going to do: he attacks the unsuspecting alien probe. Personally, I thought the whole underground bunker scene was dopey.
After being imprisoned in the metal cages, the aliens come after Cruise to gobble him up and feed on his blood. As the first few victims are selected, people scramble vainly to avoid be taken just then, even though it is clear that they will eventually be destroyed as well. But by the time Cruise is nabbed, an American soldier leaps to try and pull him back while yelling for everyone else in the cage to do the same. The group does so, and, unified, they are able to free him from the alien ship's grasp (after he's cleverly hurled grenades into it). The cage contingent was conspicuously multi-cultural.
This is a conventionally straightforward measure of the need for unity despite differences when calamity strikes. When going their separate ways, they are easily picked off, but united they are able to obliterate their common foe. I'm not a fan of multiculturalism and wish we'd do more to promote cultural values that work rather than accepting everything, good or bad. But when it's something as clear-cut as the difference between life and death for all of civilization, it is definitely good to have everyone standing together.
Nature/God takes out the aliens in the end. History favors those that have survived and functioned increasingly well for eons.
Two points: One, God is on the side of civilization--the pseudo-deity of Islamic extremism is going to be trumped. Two, memes are subject to natural selection as well (in an artificial way). The nihilist aspirations of extremist fanatics will be beaten by the progressive culture of the West. It will be a bloody struggle, but civilization will eventually come out on top. Let's hope Spielberg's prescient on this one.