Denial

Faced with the predictions of the impacts of global warming on our society, the most natural and easiest answer is denial. Some deny the fact itself that global warming is happening, or the scientific consensus that it is almost certainly caused by human emissions of green-house gases. Other recognize the overwhelming evidence, but find a variety of reasons not to act (to quote Mark Lynas: "I am not the main cause of this problem", "nothing I do makes much difference", "It is too difficult for me to change my behavior", etc...), which is a more subtle form of denial. Mark Lynas pushes the analysis even further:

"In a wider sense, one could argue that the whole economic system of modern Western society is founded on denial, in particular the denial of resource limitations. Schoolchildren are taught - and Nobel Prize-winning economics professors apparently still believe - that Earth-provided resources, from iron ore to fisheries, come into the category of "free goods", appearing as if by magic at the start of the economic process. These free goods, which include all the ecosystem services that support the human species, are considered financially valueless and left out of conventional economic accounting. The standard gross domestic product (GDP) measuring stick of national economic success totals up the values of production and consumption without considering the sustainability of the process. In a master stroke of creative accounting, conventional economic theory therefore counts the depletion of resources as an accumulation of wealth. This logic is analogous to individuals spending all of the money in their current account and counting it as income - an absurdity, but one that underpins our entire economy.
Bearing this societal dysfunction in mind, it is perhaps rather unfair to blame individuals for not facing up to climate change when the whole weight of economy and society effectively prevents them from doing so. Bob Dylan once sang about how the white Southerner who shot the black civil rights leader Medgar Evers in 1963 was "just a pawn in their game". So are we all, pawns in the game of global warming. But we are not entirely powerless, nor entirely blameless. The collective hand that moves these pawns is our own."

Mark Lynas, Six degrees - our future on a hotter planet, chapter "Choosing our future".

So there is no excuse not to act! We have some powerful tools to affect the collective hand: our votes, and our consumption patterns.