I genuinely believe that conservatives hate the ICC because they know that the US would have to answer for all its crimes if the ICC had power over the US.

Anyhow the world is changing very quickly and nowadays not doing business with the united states or not using the dollar, is less and less of a problem.

While I agree on the surface, these sanctions also include any American companies. You can’t use most email providers, because most are based in the US. You can’t use any debit or credit cards, because MasterCard and Visa are both American companies that will block your access. You can’t use any cloud storage providers, because they’re all American. You can’t have a Google account for your phone. You can’t even use a Microsoft account to log into your Windows PC.

And sure, lemmings will say that all of those are good things. We’re happy in our little “self-host everything, delete all the cloud accounts, avoid being tracked by any means possible, etc” bubble. But the average person barely even knows how to open a web browser, and panics when their password needs to be reset.

It basically forces you to live as a Luddite, because the vast majority of the internet, modern banking, etc will (at least tangentially) touch American commerce in some way. And the average person isn’t even close to being well-enough prepared for that kind of upheaval.

Is he afraid he could become the next target of an investigation/warrant of the ICC?

Not likely. The ICC rarely targets government officials from rich/Western countries, because it knows perfectly well how that'll turn out.

Also, the US is not a signatory to the Rome Statute, meaning the US is under no obligation to act on warrants or investigations issued by the ICC.

He would have to step foot in a country that is, and one that respects its obligations towards the ICC.

Unfortunately it very often leads to doing more business with China and the Won, which is very much a growing problem.

No, he's not afraid of that because the US is not a party of the ICC and the American Service Members Protection act prohibits US courts, agencies, entities of state or local government from cooperating with the ICC and further

The President is authorized to use all means necessary and appropriate to bring about the release of any person described in subsection (b) who is being detained or imprisoned by, on behalf of, or at the request of the International Criminal Court.

The definitions of the people described in subsection b are:

3. COVERED ALLIED PERSONS.—The term ‘‘covered allied persons’’ means military personnel, elected or appointed officials, and other persons employed by or working on behalf of the government of a NATO member country, a major non-NATO ally (including Australia, Egypt, Israel, Japan, Jordan, Argentina, the Republic of Korea, and New Zealand), or Taiwan, for so long as that government is not a party to the Inter-national Criminal Court and wishes its officials and other persons working on its behalf to be exempted from the jurisdiction of the International Criminal Court.

(4) COVERED UNITED STATES PERSONS.—The term ‘‘covered United States persons’’ means members of the Armed Forces of the United States, elected or appointed officials of the United States Government, and other persons employed by or working on behalf of the United States Government, for so long as the United States is not a party to the International Criminal Court.

Anyone who assisted the investigation or arrest by supplying information or funding would be breaking US law.