The idea that Charles and David Koch are liberal bêtes noires is not new. Over the past year, the elderly brothers, head of the vast Koch Industries business empire, have occupied top spot in the demonology of the left.

Across a range of activities – from the birth of the Tea Party to undermining unions in Wisconsin, to opposing efforts to curb global warming – they have been believed by many Democrats to be forever lurking behind the headlines. Now, a brilliant piece of investigative reporting by the Washington-based watchdog Centre for Public Integrity has detailed the Kochs' vast political and lobbying operations. It makes sobering and deeply disturbing reading. After all, it is one thing to believe that out there somewhere the devil exists, but reading the CPI report feels a little like being given his phone number.

The sums of money spent in furthering Koch (pronounced like the drink coke, no matter how tempting it is to rhyme it with rock) interests and power are staggering. But what is most disturbing is how rapidly they are growing. In 2004, the CPI found, the Kochs spent a "mere" $857,000 on lobbying. In 2008, that had grown to $20m dollars. Over the next two years, they then spent a further $20.5m.

The causes are varied but self-centred around the vital interests of Koch Industries such as oil, energy, chemicals and financial products. Employing no less than 30 lobbyists in Washington, Koch Industries has lobbied to change more than 100 pieces of federal legislation. They included trying to loosen regulations on potentially poisonous substances like dioxins, benzene and asbestos. They have pushed back against restrictions on carbon emissions and funded thinktanks and groups that promote efforts to discredit climate change science. They tried to soften attempts at financial reform where the Kochs operate in the derivatives market. Wherever a law touched on a Koch corporate interests, there were the company's lobbyists trying to gut, deaden or defeat any attempt at regulation.

The Kochs defenders argue that none of this should be surprising. The Kochs are fiercely political libertarians and thus believe much of government is wrong and that companies should be freed from the shackles of regulation. They openly fund libertarian organisations and, surely, have every right to promote their political ideology in any (legal) way they can. Just as every other American does.

That is true. Or at least it would be if the Kochs' activities were consistent with their proclaimed ideology. But the genius of the CPI's work is exposing that it is not. The Kochs (who, remember, oppose government intervention as anti-capitalist) should have nothing to do with the heavily subsidised ethanol industry. Yet, in fact, the Kochs are responsible for buying and marketing about one tenth of all ethanol produced in the US, effectively cashing in on government largesse. Likewise, the Kochs have vociferously opposed a cap-and-trade system for carbon emissions in the US. Yet, in Europe, the Kochs make millions from trading in emissions credits.

When fighting government regulation helps them maximise profits – even by putting the rest of us at risk from cancer-causing chemicals – they are all about libertarianism. Yet when government rules or subsidies provide an opportunity to make some money, that free-market ideology is quietly shelved.

No wonder Koch lobbyists also fought for the recent tax breaks for the rich. For the Kochs (tied at 18th place in Forbes' latest rich list) are worth $22bn apiece. The brothers must have been laughing all the way to the bank when those tax breaks got passed. Reading the CPI report, it becomes clear that the Kochs are not really ideological at all: what really motivates them is simply cold, hard cash.

So when it comes to worrying about the Kochs' influence on the political system in the US, conservatives should really be joining liberals in getting nervous.