The evidence from the natural experiment that the United States has conducted vis-a-vis the rest of the developed world is stark: having large numbers of firearms, particularly handguns, in civilian hands results in far higher murder rates than would otherwise be the case. And yes, we have murders here in Australia where I live (you have four times as many per capita than we do), but we haven't a mass shooting since 1996 when we banned semi-automatic weapons and made it harder to get pistols. So, frankly, it's you who are living in a fantasyland if you think every Tom, Dick, and Harry having a gun makes you safer.
The historical evidence is overwhelming; large numbers of handguns distributed among a civilian population leads to lots of murders; automatic pistols and/or semi-automatic rifles with large magazines lead to occasional mass shootings. Getting rid of large numbers of guns also has the effect of considerably reducing suicide levels.
If you're prepared to live large numbers of unnecessary, painful, premature deaths as a society, well, that's your choice. But no amount of "but we only support the responsible use of firearms" puffery should disguise the fact that the NRA's lobbying maintains a legislative framework that virtually ensures those premature deaths will continue.
However, if wishes were horses, then beggars would ride. The church has existed for longer than essentially any other human institution, and it will outlive all of us. Hundreds of millions of people take what its leader says seriously, for good and ill. Therefore, I don't think it's particularly important what the basis of the Pope's reasoning in his encyclical is except as that reasoning is persuasive amongst those who take Catholicism seriously.
What is important is that the Pope is saying "act on climate change", which might help to push some Catholics to do so.
Republicans have been the primary Congressional force running interference for the old space industry, either by throwing money at the likes of ATK to build rockets that will never fly, or actively blocking SpaceX from competing with the established players on contracts.
While the big government contracting model can get crews into space, it does so at such an exorbitant price it's simply not worth it. SpaceX, or more precisely the discarding of legacy design and especially legacy contracting models that SpaceX represents, at least gives us a chance of a sustainable space program because it is far, far better value for money. It's also far more in alignment with professed Republican principles, as distinct from revealed preferences from observed behaviour.
A revived crewed space program under the old model will result in bugger-all flying, lots of money wasted, and will get cancelled soon enough. Why bother?
My take: it's not the world's biggest problem, but if it's necessary to provide comparisons with earlier papers go ahead and use Lenna, go right ahead. If you just need to illustrate a technique on human skin tones, pick something else and stop needlessly pissing people off.
The White House is a (relatively) small building which faces a real, live, no-shit security threat for which armed guards and big fences are a rational, effective, and cost-effective response.
Big fences along the entirety of the United States land border and random citizens arming themselves to the teeth, by contrast, are dumb responses to the threats which the country, as a whole, faces - not least, shooting each other with guns at a rate that far exceeds any other developed country.
Leaving aside the question about whether the design was adequately verified with on-ground experiments (including static full system tests but also validation of individual engine components), why have a design that requires a human pilot on board for flight testing?
We have nasty spiders and snakes, but you don't use firearms to kill either of those. Both only strike humans defensively. Our large land animals are all herbivores; kangaroo, emus and cassowaries have a very nasty kick but they'll run away in preference to attacking you. Dingoes, despite the high-profile death of Azarea Chamberlain back in 1978, are basically wild dogs, and represent little threat to people.
We also have a collection of potentially lethal acquatic species, including the Blue-Ringed Octopus, several species of jellyfish, and some sharks. Again, guns aren't a lot of use against them.
Crocodiles, which I guess you're referring to with the giant knife reference, are the one animal that will actually try to eat an adult human. They only live in the tropical north of the country, far away from the major population centres, and any that move in near the cities in those regions are killed or relocated by professional shooters.
So, no, you don't need a gun to protect yourself from the wildlife in Australia. And despite some myths, if you want a rifle or shotgun for hunting or target shooting, or need one for farming or pest control, you can get one in Australia. You just can't walk into a gun shop and buy an AR-15 or a big-calibre handgun for "self-defence" here. And, nearly 20 years after the changes to the gun laws, that remains overwhelmingly popular here.
Incidentally, It's kinda sad how little of the topics under discussion in "Peopleware" have actually been empirically examined in the peer-reviewed literature...