The string tension on a steel string guitar can be as high as 250#, but it's usually closer to 180#. The torque is that force acting through the lever arm of the height of the strings off the top, which is usually about 1/2" So it's somewhere between 90-125 in/pounds. If the bridge is 1.3" wide, then the maximum force on the back edge, assuming all of the load was being dissipated there and the saddle was all the way at the front of the bridge, would be between 70#-95#, roughly. In fact the load is distributed all along the glue line between the bridge and the top, and that's the total static load. It doesn't produce any sound, as you can easily observe since it's there even when you're not playing the guitar.
The actual vertical force pushing the bridge in and out to make the top move is no more than about 20% of the sting tension at most, and usually much less: I'd think an amplitude of about 10% of string tension would be more like it for a hard strum. For simplicities sake any one string would be about 1/6 of that, so, say, 1.5#-2#.
This really encapsulates the problem of making a good guitar top: the top has to be stiff enough to resist the torque load over a long period of time, and at the same time light enough to respond easily to a single string.