Final answer:
The provided references, including a historical belt hook and an art sculpture, do not specify the width of a brass-tip waist belt for male soldiers. For current military uniform specifications, one should refer to the relevant military's uniform regulation manual or official publications.
Step-by-step explanation:
While the exact width of a brass-tip waist belt for male soldiers is not explicitly stated in the provided information, we can take a cue from the military context and historical artifacts. Historical objects such as belt hooks can vary widely in size. For instance, the cast bronze belt hook inlaid with gold and silver from the third to second century BC mentioned is about 5½ inches long and found in the Metropolitan Museum. However, this does not directly answer the question regarding the width of a modern male soldier's belt. Moreover, works of art, like the 'Oh! Soldier' sculpture, could suggest a general size through their dimensions but do not definitively address uniform specifications for actual soldiers.
If the answer pertains to the contemporary uniform regulations of a specific military branch, this information would typically be available in that military's uniform regulation manual or official publications.