- Wrongfully firing Acting Attorney General Sally Yates for "being weak on borders and very weak on illegal immigration." (Failure to uphold the laws of the US is a justified reason for termination. Personal ideology that runs counter the President's is not.)
- Declaring a border wall will be built between the US and Mexico. (Presidents do not have constitutional authority over border control -- only Congress has that power.)
- Declaring an import tariff on all goods from Mexico. (Again, Presidents do not have the constitutional authority to levy taxes -- only Congress has that power.)
- Declaring he would cancel the North American Free Trade Agreement. (Presidents do not have the unilateral power to cancel tariff and trade laws.)
Most worrisome to Yoo, Trump clearly not only lacks a clear understanding of the US Constitution, but also of the powers and limits to power of the Presidenty.
NYT Editorial: https://www.nytimes.com/2017/02/06/opinion/executive-power-run-amok.html?_r=0
Daily Beast: http://www.thedailybeast.com/cheats/2017/02/06/john-yoo-trump-has-gone-too-far.html?via=desktop&source=copyurl