Also your laws will help civilian building speed iirc and you will certainly get a lot of factories to help with the build up from trading away all your ressources.
US poor economy law can not be removed by political power, it can only be removed by a national focus or something.
Yes you get bonuses which is why it is a good idea to mostly use your civilian factories to build even more civilian factories but at the same time more boost in this area will contribute alot and help snowballing. US start with around 125-150 civilian factories, many are used for consumer goods which is why they only get 75 useable factories to start with.
My idea is a massive buildup of civilian factories, don't know how many factories US can support but maybe you can increase your civilian factory number into 300s with also a buildup of dockyards and synthetic plants. Then war happens you just convert most civilian factories into military factories.
US law make military factories very expansive to build, however it may be a good idea to build some early on just to be safe.
Minister that give political points can be better choice but you will lose factories by picking them (The more factories US can build the worse they get over the minister that give construction bonus to civilian factories).
US don't have perfect infrastructure which is something that should be improved (Podcat basically said once that infrastructure increase the amount of resources a province produce) to unlock more spots for factories. The same minister that help constructing civilian factories also help with infrastructure.
Another things is that I don't think US can get that far into the mobilization laws because it have to many factories compared to its enemies so the most effective way to get military factories is to convert civilian factories with the super good production bonuses to civilian factories.
Would you even research ahead of time to get say the Sherman if you planned to mainly use that as your tank in the war?
Only if I know war will happen soon because I don't think I can convert factories before war. Without many military factories tech rushing is in my opinion to expansive.