 This is the Bloomberg Green Report. The chief executive of Barclays joined a growing group of Wall Street bankers, including his counterparts at Citigroup, JPMorgan Chase, and Goldman Sachs, in saying it would be unrealistic for banks to meet the demands of climate activists who want the finance industry to abandon fossil fuel clients. The bank CEOs have all cautioned that a complete withdrawal from fossil fuels would come with unacceptable energy security risks.