[stuki]

I simply cannot fathom how the NSA could hope to intercept and physically mess with every single piece of $10 to $10,000 router sold.

If true, and I have a hard time believing it is not, either this is done at the design level (and not just on router chips), or only for big ticket backbone and/or enterprise equipment.

[Someone]

It doesn't have to be every $10 router. Plant one compromised router at each router factory, check when primary target X, Y or Z orders routers, intercept that shipment and hack each router.