Which Nation will be the first to build a real-life Mecha?

I'm saying no gas tank for 2 reasons I've come up with.

1-- A monster truck waste a full tank of gas in 30 seconds. How long do you think a mech's would last.

2-- Yeah it'd have to be huge and honestly a huge gas tank in a combat situation is never a good idea.

Infantry/anything with a gun and clear shot > Mech

Quote spoiler'd for post size.

To be fair, I'll call you biased for tanks.

Also, to be fair, I'll call me biased against tanks. There, that balances.

Any, and I mean ANY, improvements a tank cannon can have can just as easily be applied to a mecha.

An autoloader for tank shells is, in technological equivalence, a rifle clip for a rifle.

Lighter, sturdier materials? Good. Great. That'll be used across the board. Ships, Planes. Helicopters. Giant Robots.

To use RTS terms, you are mistaking a global upgrade for a single-tree upgrade.

As in, better materials would look something like this:

Upgrade name: Ceramic material
Effect: Once researched, Grants a 10% health bonus to all mechanized units.

Instead, you saw it as

Upgrade name: Ceramic material
Effect: Once researched, makes tanks uber...err, gives a 10% health bonus to tanks.

And, now a question:

If tanks are so awesome, why do we still have infantry?

Shoot a soldier in the arm, he can't fire his gun. In the leg, he can't walk. In the eye, he can't see. In the head, he dies.

Simple: Because we trade assumed weakness for ability. A mecha is, again, a giant soldier covered in metal. A squad of mechs can serve as anything from an armed escort, to a supply convoy, to a scout team, to fire support, Etc Etc. Just as normal soldiers can serve as escorts, fire support, AT/AA/AV, carry supplies, scout, and a hell of a lot of other things.

About the power issue: Nuclear, Fusion, or Fission. Anything else would be stupidly inefficient.

And, another thing.

Mecha can serve as VTOL aircraft, if it's possible to generate enough power to support large boosters.

about the last thing you said.

I think first we'd have to master the technology known as a jetpack. I don't know if their really is a functioning one. I haven't searched for it so I don't actually know so please nobody like jump me in a reply.

And mechas can get in places that tanks can, as top of buildings (if the mecha is light enough or the building sturdy enough), top of tree covered mountains, walk over large trenches and other obstacles as pits, fallen trees and other stuff that a tank has to move around it. Of course it has to be taken in consideration if the obstacle isn't larger than the leg lenght of the mecha and/or the jump capabilities.

because we want to be able to actually use the buildings after we take it over.

tank v. building-building destroyed, no gain other than removal of enemy

infantry v. building- enemy routed, building under control, can now be used as base/housing/etc

i realize thats a massive over simplification of the idea but it gets the point across

Why can't tanks go into buildings?

Maybe if we made them really, really small, and put people into them...Wait, that's powered armor.

I was saying that as a hypothetical question. The point I was making was that everything serves a purpose.

Tanks do one thing, Soldiers another, and Mecha a third.

Japan and the US are probably going to the first ones to come out with decent mechs but for me i prefer that they go for the bottom of a tank+upper body of mech combo because walkers are pretty bulky and could be tipped over easily so we work on that and come out with a gundam like mech way later in the future

A veritech could NEVER HAPPEN! Its a transformable is cool but as of now is just out of the spectrum of possible.

So do I, but my mormon side tries to become it's dictator.

Ok Well the first problem with your entire post is this: while I am a former tank driver, what I really wanted to be was a mech/battlesuit pilot. You can be biased against tanks all you want I don't care either way I look at what works best and go with that, for example I would casually say the mechs in appleseed would replace any tank ever conceived, because they are fairly inexpensive to make, they provide decent protection and firepower, they are highly mobile, you can use them in cities, give them flight capability, and for general use are superior to most other vehicles since they aren't very big targets but carry weapons big enough to handle almost anything, and they are simple to pilot. However most Mechs aren't made to these standards and the ones that are do not follow the laws of physics, sure if your universe supports that many tons of steel flying through the air at whatever speed they want and are capable of running on the ground without falling apart, then by all means, the only modern canon style weapons that can fire over 3 miles are artillery peices and that is because they fire up and over like medieval archers, so if we could build them now they would be firing straight for about 3 miles.

The first thing I see you failing to recognize is that in anime, mecha are typically using more advanced technology bases than in the real world, and aren't using real world physics because they would fall apart at the seems if they were to be able to move that fast, look at how much a fighter jet weighs (F-22 weighs about 22.5 tons) while any tank worth its salt weighs 3-4x as much (M1 weighing 71 tons) and those things fall apart under their own weight most of the time, now if you want to propel that 70 ton piece of machinery through the air at Mach you would need more than 3 times the amount of propulsion modern engines provide. Now if 70 tons moving 36 miles an hour falls apart when it drops more than 10 feet (or moves a certain distance/time) imagine what, the probably 100+ ton mech is going to do when going 500-600 MPH, let alone the rediculous speeds gundams can do. Even if we were to develope materials to make lighter vehicles the Mech would still be falling apart when moving at speed, if it had all of the things it would require to survive a battlefield anyhow.

I however am a firm believer in Veritech fighters also being a viable mecha, since they server multiple roles and are horrifyingly powerful, if stupifyingly frail, but they would replace everything but ships, and they are made of cheater-tech (stolen alien technology redesigned and improved by man) . The main reason modern fighters aren't the only thing we have is because they can't look around inside buildings while still maintaining the ability to tell neutral parties and allies from foes, while infantry can. We keep infantry for urban ops, and missions to capture and hold people and places tanks aren't very good at this because it is simply more efficient tactically and financially to send infantry to do that work.

What would you suggest the mecha's role be?

A tactical armor like a Gundam or such, would be too easily taken down by a tank with a simple cannon round to a joint. If a mecha was hit in the knee by a 120mm tank round it would become an insanely expensive weapons platform, which can again be neutralized by a following shot to the elbow. Men aren't meant to be tanks. A bipedal mech would be too vulnerable. You would need a multi-legged mech with weapons systems mounted on it to prevent aiming from being compromised due to arm failure. That is starting to sound a lot to me like a tank. In many senses, we have not reached the top of the "tank tree". The Jewish Merkava mark IV boasts the highest crew survivability rate in the world, thus becoming know as 'The Invincible Jew Wagon'. And, if tanks have reached their pinnacle, then why is it that the Abrams is no longer globally recognized as the best? The British Defender and new German Leopard are both regarded as better pieces of machinery. Another point that either I have skipped or was not mentioned is the evolution of future counter-mech technology, or use of EM Pulses. WHen the tank proved itself the king of the ground war, the tank killer was invented, specifically to exploit the tank's weaknesses, and the tanks tried to evolve to compensate. If mechs prove to be the new king of the ground war, something would come along that can exploit its weaknesses effectively. It is the way of war. As for EM Pulses, a mech platoon could be immobilized for unknown amounts of time due to fried circuitry. Granted, any friendly units in the vicinity would also be neutralized. However, if it were a modern day nation against one with mechs, our machinery still runs on petrol. The can also operate without onboard electronics. Mech fighting efficiency would be non-existent and the tanks, IFVs, artillery pieces, infantry, and whatever. All of them could wage an assault and the mechs would be able to do nothing. And don't even bring up back-up power. The circuitry itself is fried and the ability to come back online be impossible without easily doubling the cost per mech. Veritechs would be useful, though are out of the realm of possibility right now. As for power armors, I believe what would be a better choice is a layered system of ballistic gel layers, dragon-skin armor, and reinforced hard points on points such as chest, back, thighs (any non-jointed area). They would be less expensive to produce, require no power source, and provided the lightweight materials, be effectively light enough to be deployed for extended periods of time. The only downside is their still existing vulnerability to explosives, though ceramic coatings could be put on the hard point armor. The shockwaves would still prove a problem, however.

Damn, you make long posts, mate.

Here is my question: why do you consider mecha to need to be incredibly heavy?

A proper size mech is between 7 and 10 meters tall, and is often LESS armored then a tank. The functionality of a mech is designed to be a giant, metal infantryman. Mecha are more about flexibility, speed, dodging, and such.

Sure, I agree: Flying Gundam mechs are, at the moment, silly. We not only lack a good, strong material, we lack even a good power source.

When I say mechs, I ask you to imagine Full Metal Panic!'s Arm Slaves, or Code Geass' Knightmares, not Gundams or whatever.

Gundam has always been firmly placed in fiction. I mean, they use laser-based weaponry that can be dodge. The hell is that?

FMP!'s Arm Slaves, such as the Savage and the M9, happen to be light, and seem to be within out technological level, save the power source.

Knightmares doubly so...well, except the laser cannons. And that's still a matter of power.

Please do not assume I mean Gundam if I mention mecha. It makes it hard to argue.

Veritechs, on the other hand, seem equally feasible, though I'm not sure we can code a Neural-Wave AI just yet.

I make long posts because I know what I'm talking about and there is a lot of information on the subject.
Mecha need to be heavy because you don't want the average jerks with a machine gun being able to take one down, as will invariably happen, if you make it light, because I'm using real world physics, and in real world physics the ability to endure an RPG to the face requires you to be heavy.
A combat ready tank (well ok a M1 abrams with the limiter off) can move about 72 mile an hour and that thing is only 2.44 meters wide and 7.93 meters long, and it still weighs 71 tons most of which is engine, front plate, and turret, yet it still can be damaged by weapons carried by infantry, not very well but it can be.
The Veritech fighter is implausible using modern tech because like I said it is using cheat-tech, you are asking too many things from too small and too light a vehicle, as it only weighs 10 tons, this being said I wonder if they are marvel tons (10 marvel tons is a tank 100 a battleship), well they did give the weight in KG instead of tons, I suppose that means they aren't using marvel tons.

Okay, I think I'll go with Japan on this. I somehow think they have that determination to built mech but I don't think they will come out with one for military use, maybe for doing labor job helping in construction, agricultural, etc. With the influence of Astro boy making them creates human size robot, I'm sure Gundam have an impact on giant mech research. The problem might be the cost and materials involved in building them.

Also I end my comment with this interesting link.
http://www.animenewsnetwork.com/news/2008-01-11/science-website-calculates-price-of-building-gundam

Maybe Japan would build mecha like Labors from Patlabor. Labors were created to replaced heavy machines used in construction and other industries, as well military and police use.