About the second issue, the suspension of habeas corpus, the Constitution specifically says it can be suspended in such situations.
From the U.S. Constitution, Article I, Section 9:
The privilege of the writ of habeas corpus shall not be suspended, unless when in cases of rebellion or invasion the public safety may require it.
and Congress passed an act on July 29, 1861 empowering the President to "suppress such rebellion":
https://www.loc.gov/law/help/statutes-at...s1ch25.pdf
Here's a good article about the issue for those of you who are interested:
https://quod.lib.umich.edu/j/jala/262986...w=fulltext