A Financial Times column neatly summarizes the economic views of Nicolas Sarkozy. His opposition to “fiscal dumping” really means that he opposes tax competition and wants to insulate the French welfare state from global competition:

He wants the EU to move in a French direction, offering citizens “protection” from the outside world. …During the campaign, he called on the EU to protect its citizens from unfair competition from abroad, particularly
Asia, and from fiscal, social and environmental “dumping” from poorer EU members in eastern Europe. That approach is at odds with the “open
Europe” model being promoted by most northern, central and eastern European countries.