Why doesn't the US ratify treaties that have been widely ratified elsewhere?

Question

The Wikipedia article List of treaties unsigned or unratified by the United States lists, among others, some famous treaties that have been widely ratified like the Convention on Rights of Persons with Disabilities, the Convention on Biological Diversity, the Basel Convention, the United Nation Convention on the Law of the Sea (Turkey being the only other major non-ratifier here), the Kyoto Protocol and many more that have been generally ratified widely (sometimes almost unanimously) across continents but not by the US.

I am not able to see a common reason that can explain this, it cannot be framed as a North-South divide or geographical/geopolitical groupings. As pointed in comment, there are many reasons at play but can someone elaborate on few such reasons as well as check the validity of following arguments:

One convincing point I read was that given the powers of the Supreme Court of the United States, if the US ratifies a convention then SCOTUS can incorporate the treaty points to make judgements, i.e. the treaty becomes justiciable in the US. This is not so in some countries where ratification may be no more than a formality, but then again the EU also has a strong judiciary and their governments should be showing similar concerns.

There is also an argument about sovereignty raised by Republicans but I don't have a nuanced understanding of that.

Another argument was that it doesn't matter if the US ratifies, since even without ratifying treaties, the US has been making progress on its own in achieving the stated objectives of the treaty, again better than just ratifying and then forgetting.

It will be helpful if a nuanced explanation can be provided.

Answer 1

Ultimately, this needs to be analyzed on a case by case basis. Different treaties are not ratified for different reasons.

One systemic reason, however, common to all treaties to which the U.S. is a party, flows from the constitutional structure of the United States.

A President, acting alone, can negotiate and/or sign a treaty or other forms of international agreements short of a treaty (e.g. "executive agreements"). But, to ratify a treaty under the U.S. Constitution, a two-thirds majority of the U.S. Senate must vote to ratify the treaty entered into by the President in an up or down vote without modification or amendment. See U.S. Constitution, Article II, Section 2, Clause 2.

Most of the time this means that a bipartisan majority is needed to ratify a treaty in the U.S.

This is because there have only been a few brief windows of U.S. history in which a single U.S. political party which is the same as the President's political party has held a two-thirds majority of the U.S. Senate. It is also because, even then, the U.S. Senate does not have particularly strong party discipline (i.e. members of a U.S. political party in the U.S. Senate not infrequently vote in a manner contrary to the majority position of their political party).

Since it is easier for the President to negotiate and/or sign a treaty (and even to have a treaty implemented with domestic legislation which doesn't require as much of a bipartisan agreement to pass), than it is to have a treaty ratified, the gap in political difficulty means that some treaties won't be ratified.

Few other countries have this kind of systemic barrier to ratifying treaties that its head of state has negotiated and agreed to built into its political system, so non-ratification is more common for this reason alone in the U.S. than in other countries (in addition to other reasons).

This isn't the only reason for low ratification rates for U.S. treaties relative to other countries, but it is one of the important ones and is the only one that is really universal.

One convincing point I read was that given the powers of the Supreme Court of the United States, if the US ratifies a convention then SCOTUS can incorporate the treaty points to make judgements, i.e. the treaty becomes justiciable in the US.

This isn't really a major factor because only a minority of treaties entered into by the U.S. are self-executing. Treaties are basically presumed under U.S. law to not be self-executing unless a contrary intention is clearly expressed in the treaty.

ADDITIONAL POINT:

One other factor may be that ratifying a treaty is less important in U.S. law than in the law of most countries.

This is because in U.S. law, a ratified treaty can be overruled with ordinary domestic legislation (and visa versa) at any time. In contrast, in most countries, ratified treaties are superior to domestic legislation.

Answer 2

A compelling reason could be that the Untied States has little incentive to sign a treaty due to its status as superpower.

Treaties are basically protocols designed for countries to coexist with each other, to set out norms and standards that everyone follows, in order to reduce conflict and dispute. Everyone sacrifices a little personal, short-term freedom to ensure the collective, long-term harmony.

This, however, only works if the countries signing up to treaties are more or less on equal footing in terms of power. Since they recognize having no treaty would ultimately require disagreements be resolved through violence, in which case, everyone loses.

This is why Europeans are super into treaties. It's the only way for a group of small to medium sized countries (none of which are regionally dominant) to coexist.

The United States is an exception to this because a superpower does not need treaties to ensure mutual security between itself and other countries. The nature of being a superpower is that you can be completely self-reliant and still come out on top in times of conflict. In this situation, signing up to a treaty would be constraining ones own power for the sake of politeness, not necessity.

The Untied States would only have a strategic necessity to sign treaties when it is no longer a superpower, since not being a dominant player means you have to rely on international rules, norms, and protocols to safeguard ones interest in a multipolar world.

Answer 3

The US Constitution makes it difficult to ratify a treaty.

Specifically, with the requirement of having a two-thirds majority vote in the Senate (Article II, Section 2, Clause 2). This basically makes it impossible to ratify a treaty on any issue that's sharply divided along party lines. The last time either one of our two major parties had an outright two-thirds Senate majority was in 1965-67, when the Democrats got elected on the coattails of Lyndon B. Johnson's landslide victory over Barry Goldwater, briefly controlling the chamber 68-32.

The United States is by no means unique in requiring a supermajority vote to ratify a treaty. For example, the Philippine Constitution (Art. VII, Sec. 21) has very similar language that “No treaty or international agreement shall be valid and effective unless concurred in by at least two-thirds of all the Members of the Senate.” But a lot of other countries do require just a simple majority vote in their national legislature.

The US has a long cultural history of isolationism.

Part of it is due to geography. We've always been a literal ocean away from the world's other great powers, which helps insulate us from external threats. We also have abundant natural resources. Some people might even say that geography has made us overpowered. This has contributed to a national sense of self-reliance.

Part of it is due to the fact that the entire reason the US was founded in the first place was resentment over some faraway King telling us what to do. A perpetually-popular first President whose farewell address famously warned against “foreign entanglements”. The Monroe Doctrine of 1823 declared that the Western Hemisphere must be free from European interference, and served as the basis for US foreign policy for almost a century.

It wasn't until the administration of Woodrow Wilson that the US started to move away from isolation and towards greater engagement with the rest of the world, with his idea of “promoting democracy” worldwide (which is still a point of controversy due to being used as a justification for US involvement in “unnecessary” wars), and playing a key role in the establishment of the League of Nations (which the US then declined to join).

American Exceptionalism

There is a widespread belief in the United States, more common among but not exclusive to the political Right, that the US is a fundamentally “exceptional” or unique country, with unique values, and a unique destiny. Thus, policies that are popular in the rest of the world may not be suitable for the United States, and vice versa. This leads to a skepticism of international treaties, especially those that are seen as threatening US sovereignty or our status as a global leader.

Answer 4

In the US, the Senate needs to pass a Resolution of Ratification with a two-thirds majority vote. The Resolution of Ratification authorizes and advises the President to ratify the treaty. Without the approval of the Senate, the treaty would not be ratified. Even if the treaty is ratified, it's largely up to the states to implement the agreement.

Agreements like the Kyoto Protocol and the Convention on Biological Diversity have been opposed by both Democrats and Republicans. Regardless, these agreements have been implemented through various other international agreements.

The treaties are also implemented through various United Nations-accredited Non-governmental Organizations, publicly traded corporations, and other members of civil society, without approval by the Senate. Organizations like the International Union For The Conservation of Nature, which consists of politicians, governments, lobbyists, environmental groups, activist groups, and other special interest groups, claim to be "the global authority on nature and all things to safeguard it" and incrementally implement the agreements in the U.S..

Collectively, these groups implement the treaties, regardless of Senate approval, through legislative and executive actions by federal, state, county, and city governments.

The Convention on Biological Diversity, for example, authorized the production of the Global Biodiversity Assessment, which provided the scientific basis for implementing the agreement. The Global Biodiversity Assessment emphasizes fundamentally changing land use control of private property, agriculture, mining, and recreation.

Section 11.2.3.13 of the Global Biodiversity Assessment states:

“Property rights are not absolute and unchanging, but rather a complex, dynamic and shifting relationship between two or more parties, over space and time.”

The legal approach to the UN's view of property rights is discussed in Section 11.3.3.2 (pages 786-787):

“Plants and animals are objects whose degree of protection depends on the value they represent for human beings. Although well intentioned, this specifically anthropocentric view leads directly to the subordination of biological diversity, and to its sacrifice in spite of modern understanding of the advantages of conservation. We should accept biodiversity as a legal subject, and supply it with adequate rights. This could clarify the principle that biodiversity is not available for uncontrolled human use. Contrary to current custom, it would therefore become necessary to justify any interference with biodiversity, and to provide proof that human interests justify the damage caused to biodiversity".

The Convention on Biological Diversity is a legally binding agreement that establishes international law that requires the abolition of trade restrictions and subjects American citizens and institutions to judgment by the International Criminal Court. The Convention on Biological Diversity was therefore considered a threat to national sovereignty and security by both sides of the political aisle.

Private ownership of land, due process of law, and local representation are fundamental to the U.S. Constitution and national sovereignty. Therefore, the reason these treaties were never ratified is simple. They did not garner the votes necessary to become law.

See: Global Biodiversity Assessment, Convention on Biological Diversity Resolution of Ratification: Senate Consideration of Treaty Document 103-20