Can Americans have a coat of arms?
Yes. The United States has no heraldic authority and no law governing coats of arms, so any American can design one and use it. The only limit is ethical: don't take arms that already belong to someone else. Americans with British or Irish ancestry may also qualify for an official grant from abroad.
In the US, arms you design and adopt have the same legal standing as arms granted by a foreign herald, because no American body recognizes either one. The [United States heraldry](https://en.wikipedia.org/wiki/United_States_heraldry) article covers the history of American arms.
The College of Arms grants honorary arms to Americans who can prove descent from a subject of the British Crown, and the Chief Herald of Ireland has granted arms to Americans of Irish descent. Anyone else can make your own coat of arms with the free coat of arms maker