From the BBC:
Donald Trump has criticised the Harley-Davidson motorcycle firm over its plans to shift production away from the US in order to avoid European Union tariffs.
Ahem, the actual sequence of events was:
1. Trump imposes tariffs on imports to the USA, including from Europe
2. The EU imposed similar tariffs on imports from the USA
3. Harley-Davidson did the sensible thing.
From City AM:
BMW has indicated it could be forced to close its plants in the UK if it is unable to import components rapidly enough from the continent after Britain leaves the EU...
The warning from the car manufacturing giant comes hot on the heels of similar expressions of concern by Airbus and Siemens over the slow progress of the Brexit negotiations.
Last week, Airbus warned it could leave the UK in the event of a hard Brexit, putting around 14,000 jobs at risk. The firm said it would consider moving out of the UK if there is no transition deal involving ongoing membership of the single market and customs union*.
Siemens also issued stark warnings, with chief executive JĂźgen Maier criticising the government for thinking the negotiations were going to be easy and for using "unhelpful" slogans.
This cuts both ways, and is down to pig-headedness on the part of the UK government as much as the EU. Pan-European manufacturers worry they won't be able to get non-UK manufactures into the UK and won't be able to get UK manufactures into other EU Member States, or at least, nowhere near as smoothly as before, thus buggering up their highly organised and choreographed international 'just in time' assembly systems.
Overall, it's a loss to mankind.
If it made economic sense for each manufacturer to have a small, self-contained assembly system within each country (or trade bloc), they would do it anyway. For example, there are Coca Cola bottling plants dotted all over the world because it is not a particularly sophisticated technique so any economies of scale from centralising would be wiped out by transport costs. Car and aircraft manufacturing is pretty much the opposite of that, they source parts from all over the world, assemble in one giant assembly center and then re-export the finished product all over the world.
* In this context, I am not sure why the 'customs union' is particularly important, it's harmonisation of standards and import/export procedures (the main elements of the 'single market') which are the more important.