Of course, cutting an artery runs the risk of hemorrhage. If you clamp the cut arteries and veins, you allow the blood to clot and might avoid extensive bleeding. But as you know, some infant circumcision, like the traditional bris milah with periah, do not clamp the penis afterward and there can be hemorrhage. Since Jewish circumcision generally just pulls the foreskin forward and cuts, there may be less risk of cutting into the arteries. But the modern hospital methods of deep cutting and clamping probably do cut into arteries and veins alike, although there is pressure applied for several days to allow the body to heal and adjust.
Some boys never do, and experience severe bleeding afterward.
The complex vein system in the penis for irrigating this highly vascular organ basically atrophies, since its source of nourishment has been cut off from the arteries that feed it. It is inefficient, unpredictable and completely avoidable, and the extent of complications in individual men is unknown. This is hardened lymphatic fluid, which may not do him any direct harm, but it bothers him. Some people speculate that there might be a connection between circumcision, impeded circulation, and Peyronie's disease, which is where the penis becomes horribly contorted. The entire temperature-regulating system of the penis is affected.