Nice guys finish last?

Have just finished reading a paper by Dale Walton on Strategic Traditionalism, War, National Interest, and Liberal Peacebuilding. I'm not entirely sure that I can agree with all of the points that he made. Following the Machiavellian idea that states should only pursue foreign policy that is within the national interest, Walton argues that Peacebuilding, not being within the national interest, should be pursued only with extreme caution and prudence. Liberal Peacebuilding, in Walton's view, only has slight benefits for the countries that are carrying out the Peacebuilding. However, this would be true, if the economic interests were not present. US intervention in Iraq, for example, has made available Iraqi oil fields to multinational oil and gas companies including its own such as Exxon Mobil, and European companies such as BP, Royal Dutch Shell, Statoil, and Total, who have all successfully competed for contracts in Iraq. Surely, these companies, contributing to their countries' economic growth, represent a large slice of the national interest. Not to mention the US and European arms industries which supply Western militaries with weapons and military technology.
Walton argues that Liberal Peacebuilding is not within the national interest. Yes, the wars in Iraq and Afghanistan, have damaged the reputations of the US and its western allies in the world. In my view, they have also threatened the security of the next generation, as these wars have given renewed vigour to the Islamic fundamentalist cause. But, from an economic point of view, war can often be a profitable venture.
However, Walton does argue that building democracy in post war countries is not a feasible venture, and this I do agree with. In the case of Iraq, the US and its allies could meet their economic interests through simply replacing Saddam Hussein's regime with a pro Western regime. Though it would not be democracy, it would still be friendly to the interests of the US and its allies. As Walton pointed out, democracy can only be built when security has been achieved through the means of a strong state, and have existed for an extended period of time. For example, following the Korean War, it was only decades later that South Korea truly became democratic.
However, I do believe that humanitarian intervention, on certain occasions is necessary. This not only relieves a population or ethnic group from untold oppression, but it also sends a clear message to other states that the abuse of human rights is not acceptable.
This being said, the saying 'nice guys finish last' does come to mind after having read Walton's paper, and I believe that this is ultimately what he is trying to say. This is seen in the following words, "Although it may appear hard hearted, even immoral, to approach humanitarian issues as matters of national interest, there is a sound reason for doing so: strategically irrational behaviour usually is punished".