The title says it all. So many people forget that is what the Constitution says.
Yes, techology has changed things since 1789. It takes months to train a rifleman in today's US Army, and years to field a new tank or artillery piece. But it takes decades to design and build an aircraft carrier or SSBN, and the same goes for a new aircraft.
The US is currently involved in a guerrilla war (or terrorist war, or whatever) in Afghanistan and Iraq. And there are people in the US defense and policy establishment who greatly desire that the money and resources being put into a next generation fighter or into modern warships go into counterinsurgency.
I don't think that is the right solution. For a couple of reasons.
First, any money we put into Iraq or Afghanistan is like giving money to your worthless brother-in-law. All they will do is make a bunch of promises "to getta job t-day!", and then they'll show back up two days later smelling of Mad Dog 20/20 and hooker. And promising that "this da lastest time! promize!" before collapsing on what was once your couch. You get to go back to work to keep the slob fed. Same with the US in IZ and AF. We take the hard-earned resources of the US taxpayer and throw it into the empty void in the hopes that "things will work out." Screw that.
Secondly, I have no problem at all with the US defense industry (in full disclosure, I work in it). I'd much, much rather take the cash and put it in a defense plant in Ohio than in a police station in Mosul. At least the guys in Ohio will buy stuff in the local economy, will buy homes in the local area, and in general, put the dough right back into the US economy. That isn't happening in Iraq right now. We put money in, it goes 'poof' and we keep doing it.
Lastly, people forget that the United States is a maritime power. Good God people, there are pirates out there again. Not the cool kind in the movies, either. Nope, these are the kind that earn the title "scum"--murderers, kidnappers and rapists running along the seaways of the world.
Why? Why the rebirth of something everyone had pretty much placed in the dustbin of history? Easy. Ain't no cops in the neighborhood. The US Navy has been cutting back on ships since King Bush I. I am sure that there were plans to build better ships...funny thing is they were never built. So, we are stuck with a Navy, supposedly the best on the planet, that is sailing in old ships. I have no problem with old ships. In fact, there are two that need to be brought back. Today. The USS Iowa and the USS Wisconsin are sitting in mothballs. The two most powerful warships on the planet. Literally unsinkable short of a nuclear weapon--ships that were meant to fight toe-to-toe against the best the Imperial Japanese and Nazi Germans could throw against them. They are intimidating. They are huge. And we are letting them rust. For the cost of a single day in Iraq, we could put them back to sea.
Spending money, for the richest planet on earth, isnt a problem. But we need to spend it wisely.
Get out of Iraq and Afghanistan. We aren't just wasting the lives of our troops and all the other stuff; we are wasting money. Money that could be better spent on domestic concerns, like infrastucture, health care and education. If you want to spend money on defense, put it into places that will help American workers, revive American shipbuilding, and are truly defensive in nature (when was the last time a warship invaded a country? or a short-range fighter?).