Some on the left are viewing the administration's recent decisions on national security issues--e.g., withholding additional photos of prisoner abuse, or maintaining some version of military tribunals--as some sort of betrayal. Others are angry that the president's economic policies have been too friendly to Wall Street, and insufficiently populist in nature. The impulse to hold the administration's feet to the fire, and to press for the left's agenda, is of course understandable, and no one should be faulted for advocating their political views. But is it fair to view every decision that does not toe the liberal line as an abandonment of principle, or a cause for anger? That would be the right response only if you judge the president's efforts by how many times he gives the "right" answer on some series of litmus tests. To judge the president that way, however, first of all would ignore the political reality that opposing views must sometimes be accommodated in order to proceed with the most important parts of your agenda. So, for example, Congress and the President let the opposition slip in an amendment to the credit card reform bill that would allow people to carry concealed weapons in national parks. They made a judgment that it was better to get the bill passed even with a provision that the majority does not support, than to create a fight that would delay the bill and slow down action on other bills.
Perhaps more fundamentally, judging the new administration on how closely it adheres to the left's preferred policy positions would also contradict the essence of the Obama campaign. While candidate Obama did express a series of policy preferences, the more important message of his candidacy was one of reconciliation and inclusion, of changing the nature of the political process to include all voices of the American people, and at the same time reducing the influence of special interests. Judged by the standard articulated in his own campaign, President Obama by definition cannot betray his supporters merely by compromising or even reversing some of his policy positions, so long as he does so for legitimate reasons, including valid national security concerns, and also including the need to accommodate other political views. The only way that President Obama could betray the principles on which his campaign was based would be for him to act in a heavy-handed, non-inclusive way; or for him to accommodate special interests in a way that is harmful to the best interests of the American people. Therefore, while people are entitled to be disappointed with some decisions, and are free to express their disappointment, they should not be so quick to view any decision they dislike as a betrayal.
(For a similar take on whether Rachel Maddow is going off the deep end, go to this post on Daily Kos.)