For example EU gives MASSIVE amount of money into farming mostly because of French farming sector wouldn''t survive without that.
While it is true that EU gives MASSIVE amount of money into farming, it's not true, that France is the (only or main) reason.
Being able to
produce enough food to feed your population is seen as having STRATEGIC importance (for obvious reasons).
Most subsidies per farmer go into Poland, by the way.
EUROX for cars is also prime example of regulation based policies where you own companies are allowed for decades to brake it while everyone else had to do extra miles increasing prices etc. Now European cars will have to have truckload of electronic systems by 2020. While you might say it is for "safety" it is clear that this is mainly because of German car sector that doesn't want cheap cars from India (TATA) and other places, for US cars they don't even care about face and they set up high tarrifs.
Japan mostly set up tarrifs and regulate in way that making business is really hard for outsiders.
Hmmm... Which rules are "your own companies allowed to brake"?
There is 20 years old
NEDC standard for how much CO2/NoX/whatever cars can produce.
It is being replaced with
WLTP (starting September this year).
Both are applied UNIVERSALLY to all cars sold in Europe.
A number of cars sold in Europe are actually not manufactured in Europe, e.g. none of Mazdas, Ford EcoSport (India, by the way).
All the tariffs are a matter of agreement, as people watching Trump should have figured by now, one side unilaterally imposing tariffs leads to
retaliatory measures by others.
For disputes over "illegal subsidies" (or tariffs) there is WTO, here is the
ruling on Boeing-Airbus row.
Trump is challenging status quo, stating that tariffs/subsidies within EXISTING AGREEMENTS are unfair towards USA. Which might or might not be the case, but you can't prove or disprove that by cherry picking a single (or a bunch) of subsidies/tariffs on either side, it's a rather complicated picture.