  We construct a web of non-supersymmetric dualities in four spacetime
dimensions for theories with theta and Maxwell terms. Our construction mirrors
the recipe used in (2+1)-dimensions to demonstrate a similar duality for
theories with Chern-Simons terms. As in the 3-dimensional case, the web
consists of boson-boson, fermion-fermion and boson-fermion dualities, any one
of which can be taken as a seed for the remaining two. To be concrete, we begin
by constructing the basic bosonization duality which we then use to generate
the web, using an analog of the 3-dimensional massive construction given in
\cite{Nastase:2017gxr} . The resulting 4-dimensional duality web is best
understood as an extension of the, by now well-known, 3-dimensional case due to
its somewhat singular nature. We conjecture that this is the final thread in a
multi-dimensional duality web that connects low energy theories in 4-, 3- and
2-spacetime dimensions and speculate on its application to 3-dimensional
topological insulators.
