Yeah, but we sent manned missions to the Moon without any experience or "tried and tested equipment".
Actually, no.
Even if we forget about Mercury and Gemini, there were SEVERAL tests done both in LEO and on the way to the Moon, before landing occured.
Even so, the Apollo missions came within a hair's width of a disaster on several occasions, culminating with Apollo 13. Luckily, those guys weren't on the way to Mars. If the were, they'd be dead.
So... wait, we're supposed to spend billions of dollars on a program to help us figure out rocket propulsion (using essentially 60s tech, that we know works well), deep-space communications (in use for the MER rovers and voyager probes anyway, manned comms is just different data), water recycling (which you can't do in an isolated environment on Earth or even in a lab?), food production (again, will a lab not suffice?), fuel production (simple chemistry; something we've been doing on Earth for a few hundred years. Surely a lab test and good engineering would make this easy as pie), air purification (done on submarines and to some extent ISS and Mir) and radiation shielding (polythene blocks, which if thick enough should do the job fine)?
If lab tests were every good enough, the ISS would not have been build.
Besides, we have NO idea whatsoever if food production on a large scale is even possible in microgravity / reduced gravity. All systems vital to the mission must survive years of harsh conditions in space environment and must not break down. A lab test is usually done under controlled situtations, taking out the element of the un-expected.
Also, air purification on ISS and Mir isn't good enough. Air is regularly brought up to the ISS. There's no way in hell we can leave the ISS on it's own for 3 years with the systems it has. Also, submarines use electrolysis to produce fresh O2.
The deep space communications from the Mars rovers and other probes is far too slow for the purposes of manned expeditions... unless you're willing to wait for 10 minutes to transmit your 10 seconds of audio. Never mind just that... the signal needs to be strong enough that it can survive serious degradation from solar interference, and at the same time be strong enough that we don't need the most powerful deep space antennas to pick them up. Those systems are too busy as is and latelly missions have started implementing a carrier signal for easier tracking - I'm sure you've heard the one on the Phoenix lander.
Fuel production needs to be perfected in space. That means setting up infrastructure to mine ice on the Moon, melt it, purify it and produce fuel. Furthermore, long term space based storage needs to be developped. It's reasonable to expect that the output from the fuel factories will be relativelly small, which means the fuell will be accumulated over several week or months.
Concerning "60's technologies":
Why don't you use a Comodore 64?
Introduced in 1982, it had an 8 bit processor capable of 1 MHz processing, with 64 kB of RAM and a graphics card capable of impressive 320x200, 16 color output!
We know this thing works well, so why, for the love of God, would we possibly want to spend money developping better stuff?
I honestly do not see the point behind a committed lunar program due to things which we could sort out in a lab (or sometimes, as is the case with propulsion technology, stuff we already know).
Ok, so why don't you present to us your own vision of space exploration? We send a ship to Mars and land there... and then what?
I won't even comment further on the concept of actually building spacecraft on or around the Moon. Well it is a very viable (and IMO, very good) concept, the time and cost needed to develop the infrastructure to do so would be prohibitive.
An underground facility would provide shelter and and pressurized environment, where crews could quickly assemble ships, made of modules built on Earth. Such an environment would protect the crews and give them the ability to double check every system before launch, as well as giving the ship protection from possible micrometeorite damage.
Also, since you can now produce fuel right on the spot, you don't need to launch several loads of it to the Moon, for every ship that departs.
True, the initial cost of the Lunar outposts would be large, but it would quickly pay for itself - in a matter of several expeditions to Mars - which can reasonably be expected, if you wanna have a continue pressence there.