The first stage is suborbital, so that's not really an option. And when it comes to aerodynamics, on the way up it's pushing hypersonic speeds with a not-even-supersonic-friendly profile, not even the usual "nose-needle" to break the shockwave, presumably because it's having to fight gravity the whole way without lift surfaces, so can't face directly into the line of motion. Plus with the fact that it doesn't start really pouring on the speed until it's mostly clear of the atmosphere anyway.

Bottom line - it's a rocket: with minimal lift surfaces efficiency isn't really high on it's feature list to begin with. On the return trip it's free to travel at much lower speeds though - it's basically a tradeoff between air resistance and the fuel consumed to hold it in the air instead of falling like a rock. Still, fuel is currently only a couple percent of the total cost of a launch, so even if you had to double the amount used you'd still see negligible effect on the total launch cost. First they have to get rocket reuse working - once you can get a half-doze uses out of a rocket, then maybe it makes sense to start worrying about efficiency on the return trip.

That wasn't my assertion. My assertion was simply that in spite of the ability of modern planes to fly themselves we still expect and demand a human to keep an eye on things, for a variety of reasons. Malfunction response but is one of them.

Personally, I don't wish to share my roadways with completely autonomous vehicles, particularly when I'm out walking or running on said roadways, without the benefit of airbags and crumble zones. It would be awesome if technology would advance to the point that human failures (I'm looking at you, asshole who texts while driving) could be mitigated. That's the really encouraging part of these technological advances, IMHO at least.

They were never "obsolete", at least as the term is commonly used. During WW2 they were useful for all manner of things, from escort duty to shore bombardment, and the only reason you didn't see the envisioned clash of battleships in the Pacific is because Halsey blundered at Leyte Gulf and took the battleline with him in pursuit of Ozawa. If he had left Task Force 34 behind, as he should have, it would have been American battleships and cruisers clashing with the Center Force, rather than escort carriers and destroyers.

As it happened, the Allied battleships performed their envisioned missions with distinction, and even a single German battleship (Tirpitz) was taken seriously enough to tie down most of the Royal Navy's battleships until she was put out of action. It was actually pretty damned hard to sink a battleship with aircraft, even under favorable conditions, as evidenced by Tirpitz, Yamato, and Musashi. To my knowledge there was only one Allied battleship lost at sea to aircraft, HMS Prince of Wales. American battleships were damaged by aircraft at sea, but never sunk or even put out of action.

Oh Gawd, they'll be licensed like Windows:

"Car, please plot a course to Milwaukee and engage."

"I'm sorry Dave, I can't do that. Automotive Pro is limited to trips of 500 kilometers or less. Please enter your Automotive Ultimate license code."

Thus guaranteeing that it never happens, at least in the litigious society known as the United States of America.

Aerospace is held to a far higher standard than automotive ever will be, with modern planes able to fly themselves from takeoff to landing, but we still expect qualified pilots to sit in the front seat and keep an eye on things. An autonomous automobile may well have more variables to contend with than an airliners autopilot. Children don't tend to dart out in front of airliners, the physics of air travel don't change drastically with weather conditions, and airplanes are built with more redundancy than automobiles.

Even if you can account for such things, how will your autonomous vehicle handle malfunctioning sensors? Aerospace has been working at this for decades and still hasn't figured it all out.

How many parsecs does it take to travel that distance?

Biology doesn't have exclusive claim to the noun evolution:

"a process of change in a certain direction"
"a process of continuous change from a lower, simpler, or worse to a higher, more complex, or better state"

You really think that everyone swapping email with her knew that their communications were being stored on a poorly configured server kept in her house? So far, the general level of panic being displayed by her many party confidants and lots of people in the business suggests that yes, indeed, the completely absurd circumstances were indeed a secret.

No, she eventually turned over only those emails that she and her personal advisors decided to hand over. Because she chose to conduct her official government business off a badly secured server in her own house and without any IT governance from her agency, we actually have no idea whatsoever what she's decided to leave out. If she'd been actually using the system that her own underlings told her she should use in order to secure and archive her communications, FOIA requests could tell us the story. But instead, we have to trust a person who - the day she was sworn in - immediately set up a system to keep her official communication off the record.

It was illegal before, too. It's just illegal on more than one front, now.

And of course we have congressional subpoenas looking for exactly this sort of communication now because they're now aware it exists, despite earlier investigations concluding that there was no email like this at all, and she and her staff - who knew exactly what they were looking for - didn't say a peep about the existence of tens of thousands of them.

I've heard that, long term, there are two alternate plans, depending on the percentage of payload/delta-V being used: if the target orbit requires enough of the total capacity to make returning to the launch site infeasible, it will instead land on the floating barge to refuel, and *then* fly back to the launch site.

I suspect that landing at sea, while less energy intensive, is considerably more difficult - especially considering that you now need favorable weather at both the launch and landing sites to have a decent chance of success.

Tours (and for that matter, the Siege of Vienna) may have saved Western Civilization but Greece was the birthplace of it. We can never say how the Greek cities would have fared as Persian client states but it seems highly unlikely that history would have unfolded as it did if the Greeks hadn't retained their Independence. If you accept Greece as the cradle of Western Civilization then it follows that the Greco-Persian wars were decisive. In that instance it's just a matter of picking the turning point, and Salamis is the best contender. The better known battles of Marathon and Thermopylae weren't turning points, the former bought a ten year reprieve and the latter was a delaying action turned into noble and doomed last stand.

Salamis was also a naval engagement, which may lead to some bias on my part, though the West has traditionally excelled at sea, so..... :)

The Iconians did. ;)

If depends on how you define "massive"; Salamis had more ships than Leyte Gulf and was significantly more important to Western history. In fact, it was arguably the most important battle in Western history, but that's a different discussion. :)

Leyte Gulf usually wins the biggest title on the basis of personnel involved and sheer geographical scope, neither of which have a historical analogue.

This is commonly repeated but it's a false assertion. The Two-Ocean Navy Act was passed in 1940 and explicitly recognized the ascendancy of the aircraft carrier.

Yamato was deployed at Midway. She was part of the body of surface combatants (with one light carrier as escort) kept out of range for the surface action that Spruance wisely declined to permit. The deployment at Midway was a Rube Goldberg contraption that personifies everything that was wrong with IJN thinking in WW2; multiple formations scattered too far apart for mutual support and a requirement that the enemy do what you expect for victory to occur.

Neither ship was used at Guadalcanal for the same reason that the old American battleships weren't used: Neither side had sufficient tanker assets in theater to keep the old battle-wagons fueled. The USN deployed new design battleships (USS South Dakota, North Carolina, and Washington) but kept the Pearl Harbor survivors on the West Coast. The IJN used two older battle cruisers (Kirishima and Fuso) that weren't as fuel hungry as their bigger/newer cousins.

The biggest flaw with the IJN was their inferior fire control technology. This is evidenced both in surface actions (Samar being the best case study) and in the anti-aircraft role. The USN had radar directed fire control in 1942, for both surface targets and aircraft. The Japanese paid an extremely heavy price when attacking our ships with aircraft, the two carrier battles in the Guadalcanal campaign (Eastern Solomons and Santa Cruz) were Pyrrhic tactical victories at best, with most of the Japanese aircraft losses coming from AA fire.