  A brief discussion is presented assessing the achievements and challenges of
string phenomenology: the subfield dedicated to study the potential for string
theory to make contact with particle physics and cosmology. Building from the
well understood case of the standard model as a very particular example within
quantum field theory we highlight the very few generic observable implications
of string theory, most of them inaccessible to low-energy experiments, and
indicate the need to extract concrete scenarios and classes of models that
could eventually be contrasted with searches in collider physics and other
particle experiments as well as in cosmological observations. The impact that
this subfield has had in mathematics and in a better understanding of string
theory is emphasised as spin-offs of string phenomenology. Moduli fields,
measuring the size and shape of extra dimensions, are highlighted as generic
low-energy remnants of string theory that can play a key role for supersymmetry
breaking as well as for inflationary and post-inflationary early universe
cosmology. It is argued that the answer to the question in the title should be,
as usual, {\it No}. Future challenges for this field are briefly mentioned.
This essay is a contribution to the conference: "Why Trust a Theory?", Munich,
December 2015.
