Analysing Keynesian Economics: Hope or despair?

J.M. Keynes, in his publication "The General theory on Employment, Interest & Money" in 1936, advocated public sector participation in Economic activities of nations thus giving rise to the need for active public sector role in regulating the Economics of nations. According to Keynes, pure Private capitalism results in undesirable macroeconomic results. He suggested 2 types of Government roles:

1. Monetary Policy measures wherein regulation & influence was done upon the cost of capital, availability of capital & its supply.

2. Fiscal Policy measures wherein the Government shall directly interfere & participate in economic affairs of the nations mainly to gather revenue(in form of progressive taxation), borrow money(debt raising) to raise capital if needed & to spend the money in form of Public expenditure(i.e. creating public utilities & services).

If we observe the above measures as suggested by Keynes, we can see that this theory has become universally acceptable & applicable, hasn't it? Keynesian Economics thus stresses the need to have active Government role but with enough space for Private participation. This gives rise to a mixed economy.

Various heterodox school of thoughts(the school of thoughts in Economics that are against the mainstream economics) have criticized Keynesian economics. They have their valid points that role of Government has actually created an artificial economy which is regulated not by market mechanisms but by coercive participation. Agree to it. They also criticize Keynesian Economics that since 1970s, this school of Economics hasn't been able to serve its purpose of a harmonious, growing & satisfying economy rather has created may problems such as the latest Recession of 2008. Again agree.

Now, what I don't agree to is, if Keynesian Economics is so much unsuccessful, how come it could help in overcoming the Great Depression of 1930s & so many others after that? How are we still growing & are able to develop while satisfying the needs of our people(keeping aside the case of some undeveloped nations)? How have the economies of U.K., U.S., E.U. & such developed economies been able to sustain their Economic models with so much of consistency? Why crores of Economists still support Keynesian thoughts & have hope in it? Only the readers can answer this as they have to decide the ultimate outcome of my discussion.

Agree, that present Economic principles have created a lot many problems some of them which threaten the very sustainability of Economies, but these are short-term of medium-term fluctuations that "call for further active research & upgradation" of Keynesian school of thought. This is a sign of need for adding and/or modifying the underlying principles while keeping the core laws & philosophy constant.

While further highly active & rigorous research is required in this School of thought, I urge the readers, especially those who belong to the fraternity of Economics & have passion for it to go for research in this filed & develop newer & much more applicable models. This will ensure that the ideas given by Keynes do not go in vain even after serving its purpose for so many years. Do express your views.