Allport doubted that group contact progresses peacefully without qualifiers.

Evidence

Allport was cautiously optimistic about the role of contact in reducing prejudice. He began his discussion of contact by citing work by sociologists, whose “peaceful progression” model (Allport, 1954/1979, p. 261) described a series of steps through which groups in contact progress until the intergroup relationship is a peaceful one: “At first, there is sheer contact, leading soon to competition, which in turn gives way to accommodation, and finally to assimilation” (p. 261, emphases in original). But, he warned, “whether or not the law of peaceful progression will hold seems to depend on the nature of the contact” (p. 262). — , Rudman, Laurie A - On the Nature of…, 1799