There is no ELI5 answer to a question of this complexity. Seriously it happened 80 years ago and it is still an active topic for serious inquiry.

My top most opinion is Germany underestimated the Soviet union's ability and commitment to fighting.

Germany and The Soviet Union had a non-aggression treaty to divide Poland. If the Germans had abided by the agreement they would not have expended so much of their resources in the Eastern front and might have successfully controlled Western Europe.

https://www.britannica.com/event/German-Soviet-Nonaggression-Pact

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Without wanting to get too far into a massive subject: it's important to keep in mind that invading the Soviet Union was a key Nazi goal. In their minds, the land and resources were needed to make Germany strong enough to stand against the British Empire and the United States. So what looks like a strategic mistake was really a key goal of the war for Nazi Germany.

Those military planners were probably right that they wouldn't get a better chance later... Which just goes to show how far their goals were from their ability to reach them. (A mistake not entirely unrelated to the whole "slavs are subhuman, Germans are superior" thing...)

Mostly a numbers game but some pretty bad decisions were also made especially later in the war. The US was the largest industrial power by a wide margin and practically immune to attack on the mainland. Germany could never match the sheer output and in a total war the larger economy is going to win eventually.

The biggest strategic mistakes were going to war with the US when they didn't necessarily have to, choosing to fight a 2 front war and continuing to fight Britian when they had no real chance of winning quickly. Really you would need to change all 3 of these for Germany to have any real chance of winning.

Nazi Germany tried to attack the three largest empires in existence at the same time, with the assistance of two other middling powers. They were dwarfed in population, dwarfed in available resources, and dwarfed in industrial capacity. Their only hope was that the populations of those empires would be unwilling to actually fight and would surrender/negotiate for peace after a few defeats.

The military leaders in charge during the most successful stages of the war were replaced by those closer aligned with Hitler politically. They were not good enough to repeat the successes of their predecessors. Hitler also made a huge mistake of opening hostility upon Russia. The new front divided the countries resources, and Germany couldn't fully utilize the armies, and armaments of the countries they occupied as they moved east. They just couldn't move fast enough.

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This is what water towers are for. When you have a roughly 160 ft tall column of water, the water at the top will be pressing down on the water at the bottom with the right pressure for homes and apartments to use. Pumps are used to fill the water towers.

As everybody else has said they are very automated. For questions about commercial flying there's a great youtube channel called Fly With Captain Joe. He answers all kinds of questions about flying. https://youtube.com/@flywithcaptainjoe

Boeing and Airbus have about an equivalent number of aircraft in service, and both the 777 and 787 utilize FBW, as well as Embraer. So, the majority of commercial aircraft in service are FBW.

A lot of the truly huge bandwidth eaters don't have to cross the Atlantic. Heavily used video streaming services almost always have regional servers directly hooked up to major ISPs backbone networks.

Video streaming alone takes up a huge amount of internet traffic (some sources say 65%, others as much as 80%). Each 5 seconds of 1080p Netflix video eats up as much data as a typical non-video web page. 4k video consumes three times as much. When you take this out of the equation, the amount of data that needs to cross the oceans drop to a much more manageable level.

CDNs (content delivery network) also help lower the amount of data that needs to be transmitted. If you've heard of Cloudflare or Akamai, these are services that host web pages, or much of the content on them, at multiple locations across the earth.

This means often-requested data can be loaded from somewhere close to the user for a lot of web pages. These CDNs also help smaller web pages defend against denial of service attacks.

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Most urban water supplies use reservoirs of water high up so that gravity does the work of keeping the water moving. At that point, all you need is big enough pipes that the flow rate doesn't slow the water down enough to cause problems. Too much flow in too small a pipe increases the speed and thus the resistance to flow reducing the pressure at the other end (pressure is only constant at the same level when the water isn't moving). These supply pipes can be over a meter in diameter, sometimes even larger. The size steps up, the more properties are supplied be the pips - where I am its generally 15-25mm for a single house, 100mm along most streets, 300mm feeding multiple streets etc. A recent project in my city was a 3m diameter pipe from the reservoir in the hills outside the city

Depending on the terrain around the city, the main storage areas might be too low for this to work properly, in which case, you can use pumps or water towers resupplied with pumps. Particularly tall buildings may need to use pumps or their own tanks in the top of the building to ensure the pressure is maintained as they may be higher than the main reservoirs or close enough to reduce the pressure below the required level.

"Flipping burgers is a hard ass job"

Lol, bro... Stop.

Municipal water systems and water companies generally provide enough pressure from pumps and / or water stored at higher elevation or in an air pressurized storage tanks.

Taller buildings have to have their own pumps and occasionally tanks to lift and pressurize at higher elevations.

Water systems with extensive change of elevation typically have pressure reducing valves that isolate higher elevations from the lower elevation portions of the system so that the force of gravity doesn't overpressurize lower elevations and rupture pipes, and also have valves so that leaks in lower elevations don't dewater higher elevations, creating such an aggressive siphon as to implode water heaters and other tanks at higher elevations.

Yeah...about 16 last time I looked. Half As Interesting did a video on generations of cell service, and the same principles can be applied to sending data down wires...

One of the nice things about a water tower is that the pressure is not really affected by flow rate (unlike a traditional pump which has a limited power output and where the pressure drops off as flow rate increases).

Potential energy is stored in the tower. If more people turn on the tap, the potential energy just gets used faster. So long as the tank doesn't run dry, there will always be water pressure for everyone. Then a pump can slowly supply the tower during times of low use such as nighttime.

Others have covered the answer quite well.

As a network engineer since the early 1980s, I'm actually a bit surprised that there are that MANY. I would have guessed about 100.

As far as movies being streamed. They are rarely streamed over an incredible distance. Most of the time they are hosted quite close. If you are in a major city, the source is in the same city as you.

There are entire businesses based on keeping content locally cached and they are funded by the content providers.

Subterranean termites living in the soil will have instant access to the wood in your home.

Also the soil can get damp from rain/poor drainage and cause mold and mildew problems.

A slab adds a physical barrier to prevent this but it is very difficult to modify or repair anything built into the slab. For example the drain pipe.

The crawl space acts as an air barrier and allows for easier access to plumbing or HVAC systems. It also takes less concrete since you only pour in the perimeter of the house for the foundation.

They dont, there Are Water towers or tank on high enough place, you pump Water there And the Water just naturaly flow down to your house

Your home fiber link may be capable of 1Gbps. Your ISP may be artificially limiting this but the equipment is capable of this. The equipment used for the subsea cables are usually capable of 100Gbps. This is because they use better electronics, lasers and detectors. But then they do not just have one of these feeding each cable, they have a number of these transceivers at different wavelengths and use a prism to combine the light in one end and split it up at the other end. So a single fiber strand can connect several of these 100Gbps links across the ocean. They then take lots of these fiber strands and bundle them together in one cable.

For comparison a video stream is typically around 10Mbps. Your home Internet is technically capable of 100 video streams at once. The high speed links used by ISPs are capable of 10 thousand video streams. When you bundle them together with a prism you can get maybe 250 thousand video streams through the single strand. A single cable is then capable of a few million video streams. And there are around 500 of these understea cables so the total capacity of them is over a billion video streams.

You are however right that even that is still not enough and companies like Google (owner of YouTube), Netflix, Amazon, etc. have problems with the slow bandwidth of undersea cables. So they take advantage of the fact that a lot of people see the same videos and will copy the videos to different datacenters all over the world and then people will stream from their local datacenter.

Ok this helps.

Sounds like there are a lot of fancy ways to cram a lot of data more efficiently.

My baseline assumption is that two computers are typing out bytes of data one at a time and sending those individually, and then sending another. I guess i have to accept that computers have better ways of doing that

They are local pumps in various part of the system to ensure the local pressure is high enough to reach around 6 stories high while then still having enough pressure coming out the tap on the top floor. Buildings that are larger than that needs to use their own pump to pressurise it further to reach the higher floors. They often combine it with a water storage tank on the roof, to not require huge pumps to meet demand when everyone is taking a shower at the same time.