Firstly, if you want to maintain your privacy, you need to create an album on Facebook with the privacy settings set so that only you can see the pictures. You may want to call it your Political Stew album... or not. Then copy, download, do whatever you want to get any relevant pictures in to that album.
The next instructions may vary, depending on what sort of computer you are working on.
According to Taco Slim you do this:
Open the photo, right click and copy image location (if youre on mozilla) or go to properties and then copy the location, same as any photo anywhere else on the internet. It doesn't work with the Facebook mobile app though, you have to be on the internet.
If you have a Mac, like I do, you do this:
Go to the image on Facebook and hit 'control' and click your mouse pad at the same time. You will get a bunch of option. Choose "copy image address:
Then go to The Stew and click Img and insert that long link you just copied in between the Img boxes.
Voila! You can post pictures on The Stew again.
The mods should probably make this sticky.