It was very simple, really. Applying the principle of Innocence through Obfuscation, Tony Blair got everyone to tell a different story to the bloke doing his in-private (as opposed to in-public) inquiry, Dr. Iain Anderson. As a result, Dr. Anderson wasn't able to work out who was responsible for:
Taking 3 weeks to call in the Army.
A massive extension of the cull programme, which wiped out 7 million animals, part-way through the epidemic.
Closing off footpaths and not reopening them, costing the tourism industry upwards of £5,000,000.
Not considering the use of vaccination to limit the spread of the disease, despite EU recommendations.
The only person who copped for a slap on the wrist was former Agriculture Minister Nick Brown [subsequently relieved of the post], who made crucial errors and a shower of false claims that everything was under control.
Quotes from Dr. Anderson :
The evidence from Blair, his minsters and their officials "did not add up to a coherent story."
"Most of the time, people were saying they weren't present when decisions were taken. When I asked who made decisions, people replied that they were not sure. Decisions just emerged."
New Labour -- in office but not in charge of anything.