You can create your document using a template like the following (call this file.tex):
\documentclass{article}
\newif\ifinclude
\ifdefined\public\else\includetrue\fi
\begin{document}
Here is some content that is always visible.
\ifinclude
Here is some content that depends on a condition.
\fi
Here is some content that is always visible.
\end{document}
This defines a conditional \ifinclude that can either be true (\includetrue) or false (\includefalse, default). This condition is switched on/off by virtue of whether a macro \public is defined or not (using the e-TeX primitive \ifdefined). Wrapping the non-public details within your document/resume around a primitive \ifinclude...\fi conditional, you can selectively include this content or not, based on the existence of \public, which you then define at the command line. For example,
xelatex \def\public{}\input{file.tex}
produces
while
xelatex file.tex
produces

since \public is undefined.