When he thought he was on top, President Obama was too heavy-handed. He rammed through a major health bill with practically no Republican support, that disquieted a lot of members of his own (Democratic Party). But when he "had the votes," he went for "all or nothing," even at the expense of Democratic seats in one or more future Congresses
But now that he "lost" the mid-term Congressional elections, he went the other way.by making major concessions on the tax bill, without a fight. Basically, he gave the Republicans their version of the stimulus package, whether or not it was good for the country without making a try for a reasonable compromise that would have allowed him to stand up for his principles. (It is the "try," and not the "compromise," that does this.) Earlier, he expected the Republicans to do the same for him when they were out of power.
And the "kicker" to both the health bill and the tax bills is that they both defer the main issues to after the 2012 elections. This is playing politics at its worst, trying to defer the impacts of bills that may be unpopular, because you don't want to pay the political price.
This is not a political system, this is a "spoils system," to the victor go the spoils. This was a major bugaboo of the nineteenth century, that we were able to put off for most of the twentieth century, but not the twenty-first. But the total lack of regard for principle, and the sheer use of force, is what has corrupted the American political system, almost beyond recognition.