Liberalism hasn't been around in over a century. Politichic, you may enjoy this book. It's a classic in poli sci.
Amazon.com: The End of Liberalism: The Second Republic of the United States (9780393090000): Theodore J. Lowi: Books
The End of Liberalism: The Second Republic of the United States
This widely read book has become a modern classic of political science.
The main argument which Lowi develops through this book is that the liberal state grew to its immense size and presence without self-examination and without recognizing that its pattern of growth had problematic consequences. Its engine of growth was delegation. The government expanded by responding to the demands of all major organized interests, by assuming responsibility for programs sought by those interests, and by assigning that responsibility to administrative agencies. Through the process of accommodation, the agencies became captives of the interest groups, a tendency Lowi describes as clientelism. This in turn led to the formulation of new policies which tightened the grip of interest groups on the machinery of government.
The problem is, you are putting the blame on the wrong people and the wrong party.
It has been the conservative era that started with Nixon that ushered in the clientelism, regulatory capture and corporate lawyers authoring laws that benefit only the corporations.
After the assassination of President Kennedy, the Vietnam war fiasco (JFK planned to withdraw by 1965), the assassination of Robert Kennedy and the riots at the 1968 DNC in Chicago, the Democratic Party was splintered.
John Kenneth Galbraith, one of JFK's most trusted advisers predicted what followed:
For Galbraith, a trusted adviser with unique back-channel access to the President, a potential US war in Vietnam represented more than a disastrous misadventure in foreign policy--it risked derailing the New Frontier's domestic plans for Keynesian-led full employment, and for massive new spending on education, the environment and what would become the War on Poverty. Worse, he feared, it might ultimately tear not only the Democratic Party but the nation apart--and usher in a new conservative era in American politics.
Galbraith and Vietnam
In 1965 there were a few hundred lobbyists in Washington. Today there are 35,000 registered lobbyists in DC.
Two true liberal Democrats said it best:
"Harry Truman once said, 'There are 14 or 15 million Americans who have the resources to have representatives in Washington to protect their interests, and that the interests of the great mass of the other people - the 150 or 160 million - is the responsibility of the president of the United States, and I propose to fulfill it.'"
President John F. Kennedy