I agree: there are reasons why "aliens" won't suddenly land anywhere. However, I think the reasons you have cited are a bit too 'personal'. The
human race is imperfect -- at least, in its own eyes -- but such imperfections won't be visible by beings that are tens of thousands of feet in the
air -- or above our atmosphere.
Our various Social, Economic, and Political crises are only known to us. These "aliens" would know nothing unless they've had some direct contact
and/or carried out a thorough investigation of humanity
from the inside. Currently, I have found no evidence to support such a fact.
Realistically, if an "alien landing" were to cause any impact, there would have to be a visible (and large) fleet -- not the "spots on video"
variety. This is because such a meeting would be between civilizations, not countries. In the past, even human explorers sailed with several ships
(See Christopher Columbus, Ferdinand Magellan). Why then would another planet's civilization send one 2- or 4-personnel ship to Earth?
When they arrived, our hypothetical alien "fleet" would seek out a clear landing spot that could host all ships -- like a desert. There might be no
one around to see them land -- although, if the military spotted a fleet of landed ships sitting in a desert, they would scramble a substantial amount
of aircrafts to investigate. If the fighter pilots aren't trained to handle what they see, or if the aliens mistake their intentions, it could easily
escalate into a slaughter, not a war.
Alternatively, if our aliens chose to make contact with the inhabitants of this planet, they would have very few (parking) options in a city. Also,
they most likely know nothing about our ways of life; they would be unaware of the tourist spots, or other places of importance, where they can make
the "greatest impact". As such, if they landed in a humanly-significant place -- e.g. the White House Lawn, where they conveniently shake hands with
the US President in front of the Press -- you have every reason to get suspicious.
There is also the question of communication. It can't be assumed that "they" can communicate telepathically -- although there is no reason why they
can't. It would remain to be seen. But more important than communication is our visitors'
motivation for dropping in. This is a fairly-sized
planet -- small, by most comparisons -- but still large enough. It does seem to have a rich abundance of naturally-occurring minerals, and a lot of
water. These might be far more important and interesting to them than the inhabitants of the city.
For instance, if they came here to settle, they would have to examine the
planet itself, which could easily be carried out while unseen to us.
In some bodies of water, these explorers might find unusual substances, which they would eventually trace back to our civilization. At that point,
they could decide we're a threat to their intentions (of settling), and exterminate us accordingly.
There are other reasons to why aliens wouldn't suddenly land. It should also be remembered that there are reasons why they
would (and could)
suddenly land anywhere. However, we should be cautious in assigning personal bias to these causes. An extraterrestrial is not
human. Such an
unfamiliar life-form will probably not see our world as we do -- especially in terms of needing redemption. Extraterrestrial visitors might only be
interplanetary explorers; the true implications of their arrival would be left to us: if we chose to consequently create "world peace", it would be
our decision, not theirs.
I will conclude with an analogy for your introspection.
Imagine you discovered an occupied town that was built on a mountain. Of course, you are very excited by the find because, due to the town's
disadvantageous position, it has developed in isolation from the rest of humanity.
Suppose then that, instead of monitoring them from a vantage point, you decide to walk in with your arms outspread. You want to hug everyone there and
tell them just how fascinating you find them. But instead of returning your greetings, you are immediately confronted by a crowd of disgruntled
people, all who want you to solve their quarrels. Someone produces an ancient parchment, whose ambiguous contents purportedly "predicted" your
arrival.
Seems far less plausible of a scenario, doesn't it?
Cheers.