>From PDF link on web page:

http://www.antitrustinstitute.org/Archives/miceu3.ashx

As the inconsistency from one US Administration to the next might
suggest, Barnett is far from speaking for a unified US antitrust
community. His public attitude toward monopoly has at least been
consistent: the government should avoid doing anything that
might chill aggressive “competition” by a monopolist. Thus,
Barnett’s statement smacks of remorse that the US government did
anything at all to stop Microsoft’s exclusionary practices.

The American Antitrust Institute and many other observers of the
antitrust scene are far more concerned about the ability of a
monopolist to “chill competition” by erecting entry barriers that
protect the monopoly against unwanted intruders.

The EC’s position, upheld now on appeal, shows the proper concern
for practices by dominant firms that eliminate both actual and
potential competition which could benefit consumers. The EC has
appropriately targeted strategies that would have the effect of
deterring investment in innovations that might lead to a reduction
of the monopolist’s power and new benefits for consumers.