But in a letter to Papovich written from death row on May 3, 2001. McVeigh told Papovich that these documents he had sent him contained 'the final piece missing from the "why" equation.'

In a letter to Observer journalist Tracy McVeigh, the convicted Oklahoma City bomber gave Papovich's phone number and pleaded: 'Ask him specifically for my 3-page letter "why I bombed the Murrah building'.

The following is that letter which shows the build-up of anger that McVeigh had against a US federal government 'run amok' against its citizens and the politics that led to his bombing of the Alfred P Murrah building in Oklahoma City on April 19 1995 - the second anniversary of Waco.

What McVeigh wrote:

'I explain herein why I bombed the Murrah federal building in Oklahoma City. I explain this not for publicity, nor seeking to win an argument of right or wrong. I explain so that the record is clear as to my thinking and motivations in bombing a government installation.

"I chose to bomb a federal building because such an action served more purposes than other options. Foremost the bombing was a retaliatory strike; a counter attack for the cumulative raids (and subsequent violence and damage) that federal agents had participated in over the preceding years (including, but not limited to, Waco). From the formation of such units as the FBI's Hostage Rescue and other assault teams amongst federal agencies during the 80s, culminating in the Waco incident, federal actions grew increasingly militaristic and violent, to the point where at Waco, our government - like the Chinese - was deploying tanks against its own citizens.

Knowledge of these multiple and ever-more aggressive raids across the country constituted an identifiable pattern of conduct within and by the federal government and amongst its various agencies.

'For all intents and purposes, federal agents had become soldiers (using military training, tactics, techniques, equipment, language, dress, organisation and mindset) and they were escalating their behaviour.

Therefore this bombing was meant as a pre-emptive (or pro-active) strike against these forces and their command and control centres within the federal building. When an aggressor force continually launches attacks from a particular base of operations, it is sound military strategy to take the fight to the enemy. Additionally, borrowing a page from US foreign policy, I decided to send a message to a government that was becoming increasingly hostile, by bombing a government building and the government employees within that building who represent that government. Bombing the Murrah federal building was morally and strategically equivalent to the US hitting a government building in Serbia, Iraq, or other nations.

Based on observations of the policies of my own government, I viewed this action as an acceptable option.

From this perspective, what occurred in Oklahoma City was no different than what Americans rain on the heads of others all the time, and subsequently, my mindset was and is one of clinical detachment. (The bombing of the Murrah building was not personal, no more than when Air Force, Army, Navy or Marine personnel bomb or launch cruise missiles against government installations and their personnel). I hope that this clarification amply addresses all questions.

Another letter sent to Papovich stated:

"When the post-inferno investigations and inquiries by the Executive and Legislative branches of government concluded that the federal government had done nothing fundamentally wrong during the raid of the Branch Davadians at Waco, the system not only failed the victims who died during that siege but also failed the citizens of this country. This failure in effect left the door open for more Wacos.'

McVeigh went on to the window of opportunity for federal agents to be held accountable for their crimes against "we the people" was again slammed shut during the court process when the US courts held that federal agents were not accountable for 'the massive loss of lives and property as well as an absolute denial of due process.'

"Some time after the fact they received awards, bonus pay and in some cases promotions for their disgusting and inhumane actions at Waco and Ruby Ridge.

"This was exemplified years later while I sat in prison, The Ruby Ridge FBI sniper, Lon Horiuchi, was charged by the state of Idaho for his actions.

"The federal courts threw out the charges, ruling that federal agents are immune from the laws that govern the common citizen.

'The surviving Davidians were sentenced to lengthy prison terms, despite protests from the trial jurors. The primary "checks and balances" system had again failed to correct the system.

'It was at this time, after waiting for non-violent checks and balances to correct ongoing federal abuses and seeing no such results, that the assault weapons ban was passed and rumours subsequently surfaced of nationwide, Waco-style raids scheduled for the spring of 1995 to confiscate firearms.

'These rumours were so persistent and deemed so credible that some congresswoman wrote letters to Attorney-General Janet Reno inquiring as to her intents and admonishing her to call off the raids.

"As it turns out these rumours were actually based on fact.

"Through the legal process called 'discovery' the Oklahoma City bombing defence learned that both the ATF (Bureau of Alcohol, Tobacco and Firearms) and the FBI had formulated raid plans for the spring of 1995 at Elohim City in eastern Oklahoma. So for those who dismiss such concerns as paranoia you need to look at the facts as they existed at the time and further reflect that the Waco raid was not imaginary - it was a real event.

"It was in this climate then, that I reached the decision to go on the offensive - to put a check on government abuse of power where others has failed in stopping the federal juggernaut run amok.