That's poor logic. I'm not saying software is the same as a bridge or a road. I'm saying that the software that's running your car, and running the tools that are used to build bridges and cars, and running airplanes, and nearly everything else mechanical these days, is part of civilization. No, it wasn't in the past, but.. that's why it's called 'past'.
Our world is becoming increasingly interconnected, thanks to software. Medical science, pharmaceuticals, all technology is expanding at an exponential rate, none of it possible without software. "Tweak code" is a joke. Sure, the Golden Gate Bridge is more impressive looking than the code base for Autocad, but no new large-scale bridges are being built without similar software these days.
I have the utmost respect for civil engineers, mechanical engineers, and frankly all other sorts of engineers. My father was an architect, his father was a civil engineer that literally built bridges all across the west coast. My grandfather worked on (among other things) Galloping Gurdy, the Golden Gate Bridge, and the Panama Canal.
What recently seemed like futuristic cybernetics is coming sooner than you think; the barrier between man and machine is slowly (but exponentially faster and faster) being bridged with nano and biotechnology. Strong AI is coming soon as well, sooner than anyone who isn't paying attention thinks. In my opinion this is some pretty impressive engineering, none of it possible without the software building blocks behind it.
As our civilization progresses our definitions of engineering slowly adapt to fit with the technologies used. Note the word 'engine' in engineering. It's not called bridgeineering.