The question is hotly debated both in Washington, where some "neo-conservatives" are already castigating Bush for supposedly betraying the "doctrine" named after him, and in Arab capitals where ruling elites are praying for a full return to Realpolitik.

Two events, one in major the other in minor key, have helped trigger the debate.

The first was a US decision to remove Libya from the list of states sponsoring terrorism and to restore full diplomatic relations with it.

This was Realpolitik of the kind advocated by people like Henry Kissinger and Zibgniew Bzrezinski and fully justified in its own terms. After all, it is a fact that Libya stopped sponsoring terrorism and severed all its ties with terrorist groups more than three years ago. The last offices of terrorist organisations still functioning in Tripoli, the Libyan capital, were shut in the summer of 2003. Libya has also admitted responsibility for the Lockerbie tragedy and agreed to compensate the families of those who died in the crash of the Pan Am jetliner.

To underline its readiness to change course, Libya went even further by doing something that no self-respecting state would have done: handing over two of his senior security officials to be tried abroad on charges of terrorism and mass murder. More importantly, perhaps, Libya has also agreed to dismantle its nuclear programme and abandon projects for manufacturing chemical and biological weapons.

The second event, this time in minor key, was the brief interview that President George W Bush granted to Gamal Mubarak, son of Egypt's President Hosni Mubarak, in Washington earlier this month. The encounter came only weeks after the Egyptian government postponed municipal elections, and just as Egypt's association of judges was locked in bitter conflict with the government over who should supervise any future elections.

As far as Libya is concerned it has done all that it was asked to do, and for years had refused to do, long before the "Bush Doctrine" was unveiled. Therefore, it may be a safe assumption that it was the fear of being targeted for "regime change" that persuaded Colonel Muammar Kaddhafi to submit to terms that, up to 2003, he had vowed never to accept. In addition, as far as we know, the Bush administration has not given Tripoli any guarantees not to press for democratisation and greater attention to human rights in Libya.

Egypt, for its part, has no choice but to continue on the path of democratisation. The postponement of the municipal elections may be seen as one of the many zigzags on that path. Egypt may need another four or five general elections before pluralism becomes inscribed in its political DNA. What matters, now is that Egypt, under Mubarak or any of his possible successors, is unlikely to revert to the one-party system established by the late Colonel Abdul Nasser and maintained with an iron fist at least until last year. The fact that lawyers and judges can challenge the government without being "disappeared" is a sure sign o fundamental change in Egypt.

In Latin America, which has known as many despotic regimes as the Middle East, a distinction has always been made between the types of dictatorship in place at any given time.

According to Latin Americans, there are two types of dictatorship. The first is known as "dictablanda" or " soft dictatorship". The other is "dictadura" or "hard dictatorship."

Basically, a "dictablanda" is interested in maintaining its own power at home, and has no ambitions abroad. In a "dictablanda", the chief weapons of the regime are the distribution of favours, the bribing of the poor masses with government subsidies, and control of the media. A "dictablanda" does not promote any hard ideology, and thus would not set up concentration camps for dissidents. It would not drive millions into exile, and would not organise mass execution of real or imagined foes. More importantly, from the point of view of international politics, a "dictablanda" always avoids war.

In a "dictablanda", at least part of the opposition is inside the country and overboard and allowed some latitude, including participation in elections that, although far from clean, provide an occasion for dissidents to be heard.

Thus, a "dictablanda" is like arthritis: it is a constant pain for its people and could be temporarily debilitating, but does not kill them.

A "dictadura", however, is always based on hard ideology and often claims a mission to transform the entire society if not the world as a whole. It is often born with a major act of violence and terror, usually labelled "revolution" or " popular uprising". It begins life by forcing large numbers of people to flee into exile while countless others are murdered as "enemies of the revolution". A "dictadura" cannot survive without war and is thus a constant source of instability in its region.

The so-called "Bush Doctrine" is often dismissed by is critics as a forlorn attempt at imposing democracy by force. It is obvious that democracy, or any other system of government, cannot be imposed on an unwilling people by force. However, what happened in Afghanistan and Iraq was not an imposition of democracy by force. It was the use of force to remove impediments to democracy. With Taliban and Ba'ath in power, the peoples of Afghanistan and Iraq would have had no chance of even thinking of a different system let alone trying to build one. Now, although they may end up building not a democracy after all, they have that chance.

Both the Taliban regime and Saddam Hussein's tyranny belonged to the "dictadura" category and, like most other regimes in that category, could not be changed without the use of force.

However, this does not mean that the "Bush Doctrine" should be pursued with exactly the same methods in the case of those regimes that could be described as "dictablanda".

In studying the application of the "Bush Doctrine" to the Middle East, it is important to understand which of the existing regimes belongs to which of the two categories presented above. It is obvious that there may be times and occasions when a democracy can forge a tactical alliance with a "dictablanda". No such alliance is possible with "dictadura" regimes, especially now that the end of Cold War has removed the necessity of even considering that option.

The "dictablanda" regimes should be encouraged to introduce reforms, broaden their popular base, and open the public space to different views and aspirations. Relations with them could be described as "critical coexistence". Because they do have internal mechanisms for change, there is no need to seek a deus-ex-machina stratagem in their case. The "dictadura", however, must be regarded as strategic enemies and thus exposed and opposed at all levels, including that of the dreaded regime change.