:The MOS does not say "intros normally have 4 paragraphs". WP:LEAD says "the lead should contain up to four paragraphs". WP:LEAD#Length says "3 to 4 paragraphs" for an article of this size. I don't oppose adding new sections but keep in mind that the cultural legacy/impact includes things like the dawn of the atomic age, impact on warfare, the Cold War, etc. Summarizing this in the lead will be difficult. The NYT article strikes me as wartime propaganda and only interesting as a footnote, but perhaps contemporary press coverage should be considered part of the cultural impact as well.