No, Americans have a strong Constitutional right to move freely within the country, with large quantities of consistent court precedent on this matter in diverse situations. Suspension of this right requires both individual due process and compelling government interest (e.g. imprisonment for a serious crime). It is on the same tier of rights as freedom of speech in the US. The Constitutional authority simply isn't there for the Federal government to ban travel, and any attempt to do so would be met with an instant court injunction.

The courts have also consistently rejected overly clever de facto travel bans via regulatory mechanisms intended to prohibit the use of common modes of transportation. Courts have taken a very dim view of arguments, which the government has made in the past, that e.g. free travel can effectively be restricted to walking. American courts have ruled in the past that the right to travel extends to the use of common modes of transportation.

If fundamental Constitutional rights could be suspended every time the government claimed an emergency, Americans would have no rights in practice. There is no allowance for the blanket suspension of fundamental rights by reason of public emergency in the US.

Trump is already considering domestic travel bans, they can always find an "exception" to the constitution like they did after 9/11.

https://www.usatoday.com/story/travel/airline-news/2020/03/1...

Except that they did not institute a travel ban after 9/11. They temporarily suspended air travel in order address manifest safety and security deficiencies in the US air travel system. The FAA has grounded fleets many times under similar authority. The highways were still open.

That is a very different legal authority than de facto blanket bans on free movement of Americans, which is expressly disallowed by the Constitution. This has actually been adjudicated several times in the Supreme Court, which has consistently rejected attempts by the government to use regulatory technicalities to deprive people of their right of free movement via common modes of transportation even subject to due process.

This is not new territory, there is extensive court precedent surrounding the right of free travel in the US. It is on the same tier of right as freedom of speech in the US.

Congress has the authority to regulate interstate commerce.

That is not applicable here. The US Supreme Court has repeatedly asserted that freedom to travel in the US is a fundamental right like free speech; regulation of interstate commerce is prohibited from violating those rights. Suspension of that right requires a narrowly targeted and compelling government interest, blanket prohibitions are prohibited, and requires due process for affected individuals.

In other words, "you might have COVID-19" has the same authority granting power as "you might be a terrorist" or "you might be a child pornographer", which is to say, very little absent specific evidence.

I have zero faith in the current federal and supreme courts upholding those rights. Stare decisis is basically dead and a full third of the judiciary are federalists or federalist-adjacent.

Also, I think you drastically underestimate what can be legally done under the aegis of "you might be (insert undesirable class here)".

Yes to both, since the case numbers will continue to increase exponentially.