I don't know much about Japanese politics, but I'm pretty sure that the Democratic Party people who were in charge before Abe were basically pursuing austerity policies that resulted in disaster for the Japanese economy. Abe was elected on a platform of Abenomics, basically expansionary economic policy, and while he didn't implement the policies as much as he should have, I certainly don't blame the people of Japan for giving him a chance. Of course, Abe's party is also far worse on social issues and much more nationalistic than the Democrats, so I may have been forced to vote Communist.
Japan's basically been following a roughly Keynesianist path since the bubble burst in the late 80s, with the 民主党 (LDP) governments keeping the economy afloat with deficit spending. This aids the economy as a whole as well as construction and many other sectors. The LDP is conservative (i.e. preserving things) in a wider sense, protecting and propping up the current Japanese corporate sector and wanting to jump-start the economy with reforms and other measures. The Abenomics program, while certainly quite above and beyond what past the scale of what has been attempted or accomplished by past DPJ and LDP governments, is not without precedent.
