The nature of FTAs is to offer free trade only to members, not to non-members. Thus, FTAs are two-faced: they ensure free trade for members and (relative) protection against non-members. First-year students of international economics would be asked to shift to a different field if they could not grasp this elementary and elemental distinction, and yet today's politicians imagine themselves to be statesmen endorsing free trade when they embrace these inherently discriminatory PTAs.
As PTAs proliferate, the main problem that arises is the accompanying proliferation of discrimination in market access and a whole maze of trade duties and barriers that vary among PTAs. I have called this outcome the "spaghetti bowl" phenomenon. (I must confess that I once used this analogy in an after-dinner speech when the chairman was an Italian who did not quite share my difficulty in handling spaghetti and seemed genuinely puzzled!) Mr. David de Pury, a distinguished representative of the globalized private sector and the chief executive officer of ABB, Switzerland, is among the renowned executives who have expressed themselves in public for a precisely on this point and on the advantage, even the necessity, of having uniform nondiscriminatory rules and barriers. I endorse this objective, which only multilateral WTO-sanctioned treaties make possible. In view of its importance, let me say a little more on this question.
International Trade Law | Law
Jagdish N. Bhagwati,
Preferential Trade Agreements: The Wrong Road,
Law & Pol'y Int'l Bus.
Available at: https://scholarship.law.columbia.edu/faculty_scholarship/3574