Good sensible questions:
"Hasn't there been a fairly much steady increase in industrial and transportation-related CO2 emmissions ever since the beginning of the industrial revolution...in other words from the 1800s right up to now?"
Actually, there has been an exponential increase in CO2 production. That is, the production is not "steady" it is ever-increasing in both volume and rate (mirroring the exponential human population growth and energy consumption). In addition, there are tremendous positive feedback mechanisms. A little additional CO2 may increase temperature a little, which thaws just a little permafrost, which releases more CO2, as well as the more potent methane...and so on, accelerating the process.
"If so, and if global warming is so much due to CO2 in the atmosphere, then why have we not seen the world getting steadily warmer throughout the entire history of our industrial revolution?"
Sure, it's complicated and one can easily point to years where the temperature dropped a bit, but the long-term trend is very clear, and it is based on a multitude of both direct and proxy measures.