-&gt;It&#x27;s no different than painting pin-up girls on on your B-17.<p>Yup, my first thought. Then I started googling and found this about how apparently writing on weaponry seems to be an ancient practice.<p><a href="http:&#x2F;&#x2F;www.britishmuseum.org&#x2F;research&#x2F;collection_online&#x2F;collection_object_details.aspx?objectId=399876&amp;partId=1&amp;searchText=sling+bullet+inscription&amp;page=1" rel="nofollow">http:&#x2F;&#x2F;www.britishmuseum.org&#x2F;research&#x2F;collection_online&#x2F;coll...</a><p>Relevant reddit thread:
<a href="https:&#x2F;&#x2F;www.reddit.com&#x2F;r&#x2F;AskHistorians&#x2F;comments&#x2F;1lmzov&#x2F;is_there_a_history_of_soldiers_writing_messages&#x2F;" rel="nofollow">https:&#x2F;&#x2F;www.reddit.com&#x2F;r&#x2F;AskHistorians&#x2F;comments&#x2F;1lmzov&#x2F;is_th...</a>