Do you HAVE to get a UK license?

Hence why the UK hasn't done it.
UK - Excuse me US, would you like to have a reciprocal agreement?
US - Errr, you'll have to ask each individual State.
UK - Well, in which case we'd need to get agreement with every single one. Get them to call us.

In the present times it would go different:
1. Belgium and Germany would just forward their US agreements to Brussels (EU).
2. EU would recognise them and they'd be valid EU wide.

No need for double work within EU framework. After all, any EU emissary is entitled to represent UK, in the absence of UK representation for that issue, by the same coin that UK citizens can resort to any EU embassy in the absence of a similar UK facility. When EU officially accepts the forwarded agreements, there is no reason for UK to disenfranchise them. How else did I (as so many others) get a bona-fide EU license from an American one. When I go to non EU countries, they accept it as an EU license for all purposes. Period.

By this token, US licenses are theoretically already valid everywhere in Europe, but ofcourse in a moot manner at the discretion of pencil pushers, and at your own peril. As such it's more an internal EU issue, rather than a UK-"each US state" issue. To be or not to be (an ally), that is the question.

I am glad you mentioned asking if we will be covered while driving someone else's car.  Here it is automatically assumed you can drive pretty much any car.  I am not sure I would have thought to ask that.

Thanks!

Most "Fully Comprehensive" (All-Risk) insurance policies will allow driving of friends' cars, also known as "permissive driving". Indeed while driving a friend's car you'll usually only be covered as a third-party policy (insurance only pays if it is other people's fault). I'm not exaggerating that you might be shocked at excessively high priced insurance policies, and suggest you do an online research or ask around for expat insurance policies that will be drastically cheaper and more in line with reason. Good luck. 

Germany don't have full reciprocation, it's only with certain States.
http://www.german-way.com/for-expats/living-in-germany/german-drivers-license-reciprocity/

Germany don't have full reciprocation, it's only with certain States.

That's true. Belgium and Austria do though, and we can only hope the EU government will soon forward the Belgian agreements for EU wide adoption. There are simply too many perfectly good American (and prolly even Asian drivers) being used as cash cows for the driving industry, due to the mere technicality of not having an EU wide agreement (which should actually be the authority in charge). It never hurts to hope for mutual progress. I guess we'll put that on the next US-EU summit conference todo list.

I became a much better driver after taking a few lessons and doing my test in Britain. I am shocked now, every time, when I come back to the US and drive on the roads. Styles of driving vary significantly, I feel much safer on UK roads and I don't think making people take the test is a bad thing at all.

DH had to take the written and road test in Virginia at age 60 back in 2000....and he had been driving in the UK since 1957.

I got my first license in NC in 1964
I got my second license in Vermont in 1967 (and had to turn in the NC license)
I was re-licensed in NC in 1970 when I moved back (and turned in the VT license)
I got my third license in Indiana in 1973 when I moved there (and turned in the NC license)
Got another NC license in 1981 when I moved back (and turned in the IN license)
Got my UK license in 1993 after passing the road test and correctly answering the then-simple "questions on motoring matters"
I got a Portuguese driving license when we lived there from 1995-1998
Changed my address on the UK license when we moved back in 1998
Got a Virginia license when we moved there in 2000
Moved back to the UK in 2011, and reported to VA DMV that I was no longer resident in VA, and that license was cancelled

The UK extends the courtesy of allowing an American to drive for 12 months on a US license; they aren't obliged to do that. Every state where I lived required me to get a license within a much shorter time period, and I seem to remember that I had to take a road test in Indiana. Definitely had to take the written test in VA.

If you move to a new place, you should expect to be licensed to drive in that place, and passing a test does not seem to be an onerous requirement particularly when switching to a RHD car and the left side of the road.

eatoomey and vadio, I thought I was alone on that side of the fence! 

It does suck to have to take a test when you're not a new driver, but I did learn a lot in my lessons and it was nice to brush up on maneuvers (parallel parking.... yikes), get rid of bad habits I'd developed and learn new skills.

In the US, I'd never been told to use the 'emergency brake' except when on a steep hill or when parked. In the UK, I was taught (by both DH and my instructor) to use the hand brake whenever stopped on a road - if you're rear-ended, it will prevent you hurdling into the next car as much as you most likely won't have the sense or ability to keep your foot on the brake in an accident (and if the next car has got their handbrake on, it will stop them from hitting the next car as hard.... and so on). A minor thing to do (but admittedly a big task to get in the habit of) but I think I'm better off after having learned it.

Driving is different here and it's important to learn the rules of the road. Driving has also changed since I took my test (and I know I'd forgotten a bit), so it was good to learn/relearn new skills.

I got my first license in NC in 1964
I got my second license in Vermont in 1967 (and had to turn in the NC license)
I was re-licensed in NC in 1970 when I moved back (and turned in the VT license)
I got my third license in Indiana in 1973 when I moved there (and turned in the NC license)
Got another NC license in 1981 when I moved back (and turned in the IN license)
Got my UK license in 1993 after passing the road test and correctly answering the then-simple "questions on motoring matters"
I got a Portuguese driving license when we lived there from 1995-1998
Changed my address on the UK license when we moved back in 1998
Got a Virginia license when we moved there in 2000
Moved back to the UK in 2011, and reported to VA DMV that I was no longer resident in VA, and that license was cancelled

While I am in some awe of a list achieved with such an impressive pragmatism, I feel differently about the necessity for hoop-jumping exercises. Fortunately I managed to jump through in the end, but a spirit of empathy moves me to commiserate with those still on the other side.

If you move to a new place, you should expect to be licensed to drive in that place, and passing a test does not seem to be an onerous requirement particularly when switching to a RHD car and the left side of the road.

That depends on the individual I guess. I have traveled far and wide and never felt any shortcoming in my Oklahoma driver license, even whenever driving in Left traffic such as in Japan, Malaysia, Thailand, India and of course UK. Admittedly I had  taken a short training and pursued a hobby of rally driving during college years, and perhaps that's why I felt a little more confident than the average city driver. Moreover it's not so much having to do the test again that's putting me off, as being treated as a new driver after successfully getting the license that would put me off. That would result in an undue spike of my insurance rate, which seems quite unjust.

Personally I feel that with a few general tips in a thin travel guide, any American driver is good to go on UK roads. (Much like the AA booklet for UK drivers to prepare for mainland Europe that drives on the right, much as in US). Oh well, all's well that ends well.

if you're rear-ended, it will prevent you hurdling into the next car as much as you most likely won't have the sense or ability to keep your foot on the brake in an accident (and if the next car has got their handbrake on, it will stop them from hitting the next car as hard.... and so on).

But the physics of this.....

The energy, according to Newton, must be transferred. It goes somewhere. By not allowing the transference to be spread out over the movement of your car (and perhaps to a few ahead of you), doesn't it mean a more intense crash? Wouldn't your head snap back harder?

I am reminded of a "winter tips" article I read once regarding radiators. The tip was to not hang stuff on your radiator to dry, nor to put a couch or chair in front of the radiator. I think it suggested putting reflective sheeting (or tinfoil wrapped cardboard) between the radiator and the wall.

I see where they were going, and in fact if you have a very poorly insulated wall, the tinfoil trick might help. But in actuality the heat coming from that radiator is not going to magically be absorbed and negated by a towel or a chair. It may take longer to radiate into the room but it must eventually do just that.

But the physics of this.....

The energy, according to Newton, must be transferred. It goes somewhere. By not allowing the transference to be spread out over the movement of your car (and perhaps to a few ahead of you), doesn't it mean a more intense crash? Wouldn't your head snap back harder?

Hmmmm.... hadn't thought of it that way...... but it does seem like taking the brunt of the push from behind could be better than being pushed into oncoming traffic or cross traffic at a junction where you could be hit at an even higher speed. Depends on the situation, of course.

Well yes if you were at a level crossing with an on-coming freight train, it would probably be better to just take the rear end smash full-on than to be nudged out onto the tracks.

Too, I bet they do sort of a cost analysis thing. Two cars buggered pretty badly is cheaper than 10 with slightly crumpled bumpers.

Moreover it's not so much having to do the test again that's putting me off, as being treated as a new driver [my bold] after successfully getting the license that would put me off.

This. It permeates the experience, from driving instructor attitudes, to the way you're treated by insurance companies and officialdom, to the aftermath of getting your brand new UK license – whereby you continue to be treated as a newbie for two years (speed twice and you have to start all over again; easy answer of course is to not speed, but it's still rather draconian) and up to three (can't teach/chaperone my wife in our car because as a 'newbie' I'm not experienced enough; thus she has to pay an instructor for every minute spent practicing for her practical).

My insurance almost halved after the first year. That's a lot of money wasted.

If you move to a new place, you should expect to be licensed to drive in that place, and passing a test does not seem to be an onerous requirement particularly when switching to a RHD car and the left side of the road.

I get Do as the Romans do, up to a point; I just think there is room in an already quite expansive set of laws to make room for non-newbie newbies.

As to RHD on the left side of the road, EU license holders and many others (including Canadians, who drive in similar conditions as most Americans, at least in terms of road space) have the same issue, yet are allowed a simple exchange.