Is the US completely unprepared...?
 

I have needed to travel through numerous airports in Europe, Asia and now have entered the US yesterday (all these travels in the last 7-10 days).
All airports - heavy screening, notices everywhere - thermometer checks are almost universal.

Still on arrival in the US - its like there is absolutely no check for incoming visitors from overseas.
WHY?

The CDC had some serious delays with rolling out tests which has in turn delayed testing and thus monitoring exactly how much the virus has spread in the US. There are theories that the numbers reported are artificially low because of this. Given the reports from many healthcare workers across social media about how frequently testing has been denied... I would say yes, the US is fairly inadequately prepared.

The US (and also the UK) seem to be taking the approach that temperature checks at airports aren't useful. I have a mixed opinion on that because it involves method, follow-up, and understanding incubation periods. Every measure taken will not catch every case of course. But most entities want to get the best "bang for their buck" (catch the most while spending the least amount of money, or even better/worse, making the most money out of the entire situation (depends on your conspiracy theory levels here)). There is also the friction between Federal and State control. Conservatives control the Federal level which means a White House culture of small Fed, big State. So they prefer States to handle things. So, States have to handle things. Even big things that affect the entire country. This is partially the result of that. (Airports are Federal...? A mix of both? Property is State, Governance is Federal? Something like that? I've never been clear on this distinction). Anyways, since the internal operations are supposed to be from the Federal level, it's a mess. Because our Federal level response is doing... poorly. Lack of resources, lack of clear direction, lack of anything that resembles rationality. It's just a mess.

As a result, there's pretty much no unified approach in the US. It's been down to individual airlines to cut services as they see fit to various places (except in the case of China or other places that seem to fit the US admin agenda, at least as of this point in time, 11.51GMT 10.03.2020). They've raised travel advisory levels for US citizens in certain countries but have only barred travellers from far fewer places (no restrictions on anyone from France, Italy, Germany, Japan, etc; no advice for self-isolation for any such travellers - at least not at the federal level).

Individual states are issuing their own warnings. And this is something that should be led by the CDC as there are no restrictions on movement within US borders. It's kind of ridiculous that someone can land in say, Miami, be told they must self-isolate, and then just drive or fly up to Georgia where the rules are different. And there's nothing to stop them. And they may have come from somewhere that's been heavily exposed.

Individual states have also had to resort to developing their own tests given the faulty and bottlenecked rollout from the CDC.

I hope that answers some of your questions.

A couple of things to think about:

How much of the low incidence count of the disease in the US was due to cutting off air travel to the US from visitors to China 5 weeks ago? Surely that had an impact?

Sadly, the CDC was late in rolling out a test due to it not meeting standards for false-positives and false-negatives. Bit iut makes me wonder how tests in other countries compare? Are some countries that rushed out tests under-counting or over-counting?

There are still flights from China to the USA every day and there have been since the start of the outbreak. If I pay 5153 RMB I can fly from Shanghai to LA tomorrow afternoon. I think much of the low incidence count in the USA is due to not testing people. You don’t test then all is good. Thailand similarly didn’t ban flights from China until 2-3 days ago and they have very low numbers, they don’t test either. It’s like magic.

Is the US completely unprepared...?

Yes

Complete bunk. More people enter this country every day with other communicable diseases than COVID-19. More people die every day in the US from influenza than COVID-19. This hysteria has to stop. The efforts being made around the world will curb this problem. Washing your hands 20 times a day will go a much longer way towards stopping the spread than temperature checks at our borders.