Excerpt:
"At least one of the docu­ments under review was designed to imple­ment the emer­gency author­it­ies contained in Section 706 of the Commu­nic­a­tions Act. During World War II, Congress gran­ted the pres­id­ent author­ity to shut down or seize control of “any facil­ity or station for wire commu­nic­a­tion” upon proclam­a­tion “that there exists a state or threat of war involving the United States.”

This fright­en­ingly expans­ive language was, at the time, hemmed in by Amer­ic­ans’ limited use of tele­phone calls and tele­grams. Today, however, a pres­id­ent will­ing to test the limits of his or her author­ity might inter­pret “wire commu­nic­a­tions” to encom­pass the inter­net — and there­fore claim a “kill switch” over vast swaths of elec­tronic commu­nic­a­tion.
...
The records indic­ate that at least one pres­id­en­tial emer­gency action docu­ment pertained to the suspen­sion of habeas corpus.
...
Restrict­ing the use of U.S. pass­ports — a repor­ted feature of some early pres­id­en­tial emer­gency action docu­ments — remained on the table as of 2008. Records gener­ated by the Bush admin­is­tra­tion’s review high­lighted a provi­sion of law from 1978 that allows the govern­ment to curtail inter­na­tional move­ment based on “war,” “armed hostil­it­ies,” or “immin­ent danger to the public health or the phys­ical safety of United States trav­el­lers.”
...
A national emer­gency declar­a­tion unlocks enhanced author­it­ies contained in more than 120 provi­sions of law. Bush invoked several such author­it­ies, but several dozen others were — and still are — avail­able to the pres­id­ent as a result of Proclam­a­tion 7463. Presum­ably, the refer­ence to the proclam­a­tion during the admin­is­tra­tion’s review implies the exist­ence of docu­ments designed to imple­ment other stat­utory emer­gency powers, which run the gamut from anodyne to alarm­ing, nearly four years after the attacks.

• • •
As with any archival exped­i­tion, the silences are often the most telling. William Arkin, a noted expert on PEADs, reviewed the new mater­i­als disclosed by the library and observed that they relate primar­ily to civil agen­cies — few, if any, touch on the role of the milit­ary in times of crisis. He suggests that this “black side” would have been discussed at a higher level of clas­si­fic­a­tion. By implic­a­tion, the most daring claims to pres­id­en­tial power may have been entirely excluded from this tranche of docu­ments."