Ignatius has a naive idea of how the Nobel Prize is manipulated by Russia using embarrassing information on prior winners and others to get nominations for Russians. A prize for Putin would be put down to manipulation by Putin. Putin would take credit as an intelligence man not as a man of peace for such a prize.
Moreover, the Nobel Prize foundation as a whole is a private legal entity that could face investigation for its role as an accessory to nuclear proliferation by these means. Russia would interpret a prize for Putin as coming from the total risk of the Nobel Prize foundation to a criminal investigation.
Swedish prosecutors have shown they will investigate the Nobel Prize Foundation and Committees.
October 23, 2012 show at about 30 to 34 minutes into it roughly.