14th Amendment Section 3.

No person shall be a Senator or Representative in Congress, or elector of President and Vice President, or hold any office, civil or military, under the United States, or under any state, who, having previously taken an oath, as a member of Congress, or as an officer of the United States, or as a member of any state legislature, or as an executive or judicial officer of any state, to support the Constitution of the United States, shall have engaged in insurrection or rebellion against the same, or given aid or comfort to the enemies thereof. But Congress may by a vote of two-thirds of each House, remove such disability.

This is the subject of the Penn Law Review article (which I can’t access) and a new article in The Atlantic by Judge Ludwig and Prof. Tribe which I also can’t read as behind a pay wall, four learned constitutional scholars, which I am not. Thus caveat emptor. 

On the face of it and unless the bolded was intended to encompass the office of President I don’t see that disqualifying Trumpie. 

A complete textual consideration does not support disqualification from the presidency: "Senator", "Representative", "or ELECTOR of President and Vice President. They use the term "President", if they had meant to disqualify a person from becoming president they knew the language to use.

And a brief contextual consideration does not support the argument. The 14th A is one of the Reconstruction amendments. The term "state" is used thrice. By Section 3's language in toto and by historical context this clause is aimed at the people of the defeated Confederate States of America who engaged in the Civil War against the victorious United States, not at anyone who is running for president. It is not disqualifying of Trumpie, imo.