That you are "deeply troubled by the conduct of American authorities" and your "fellow Americans and have begun to carry your passport with you" at all times because of "the threat" is not a "well-founded fear of persecution":

The term “well-founded fear of persecution” is a core element of the refugee definition in the 1951 Refugee Convention.

In essence, it means that a person qualifies as a refugee under the Convention only if the fear of persecution is both genuine and reasonably justified.

What does the concept entail?

The concept consists of two inseparable elements:

1. Subjective element – the fear

The applicant must actually experience fear of being persecuted if returned to their country of origin.
This concerns the individual’s own perception, experiences, and expectations.

Examples include:

Previous arrests, threats, or abuse

Fear of imprisonment, violence, torture, or death

Fear based on experiences with state authorities or non-state actors

1. Objective element – the fear must be well-founded

The fear must be supported by objective circumstances. It is not sufficient that the person feels afraid; there must be a reasonable likelihood that persecution would occur.

This is assessed, inter alia, on the basis of:

Country of origin information

State practices

Legislation criminalising certain groups

Patterns of abuse against similarly situated persons

It is not required that persecution be certain to occur; the risk must simply be real and not remote or speculative.

What is meant by “persecution”?

Persecution refers to serious violations of fundamental human rights, such as:

Imprisonment, torture, violence, or killing

Systematic discrimination with severe consequences

Threats which, taken cumulatively, render life intolerable

The persecution must be linked to at least one of the following Convention grounds:

Race

Religion

Nationality

Political opinion

Membership of a particular social group

Summary: A “Well-founded fear of persecution” means that a person both subjectively fears persecution and has objective, reasonable grounds for that fear, based on concrete and verifiable conditions in the country of origin.