Con­gress will gath­er noon­time Mon­day to cer­ti­fy Pres­i­dent-elect Don­ald Trump’s elec­tion un­der the tight­est na­tion­al se­cu­ri­ty lev­el pos­si­ble. Lay­ers of tall black fenc­ing flank the U.S. Capi­tol com­plex in a stark re­minder of what hap­pened on Jan­u­ary 6 four years ago.

What To Know:

What to ex­pect: With pomp and tra­di­tion, the day is ex­pect­ed to un­fold as it has count­less times be­fore, with the ar­rival of cer­e­mo­ni­al ma­hogany box­es filled with the elec­toral cer­tifi­cates from the states.

New changes to look for: Un­der changes to the Elec­toral Count Act, it now re­quires one-fifth of law­mak­ers, in­stead of just one in each cham­ber, to raise any ob­jec­tions to elec­tion re­sults. With se­cu­ri­ty as tight as it is for the Su­per Bowl or the Olympics, law en­force­ment is on high alert for in­trud­ers. No tourists will be al­lowed.

Har­ris to pre­side over count­ing: As is the re­quire­ment for the vice pres­i­dent, Har­ris will cer­ti­fy her own de­feat — much the way De­mo­c­rat Al Gore did in 2001 and Re­pub­li­can Richard Nixon in 1961.

The four year an­niver­sary of the Jan. 6 at­tack on the U.S. Capi­tol is be­ing marked Mon­day by a num­ber of con­gres­sion­al De­moc­rats, in­clud­ing cur­rent and for­mer lead­ers as Re­pub­li­cans re­mained most­ly silent as they pre­pare to cer­ti­fy the elec­tion of the man who in­cit­ed that very mob.

Rep. Nan­cy Pelosi, who was speak­er when the in­sur­rec­tion hap­pened, marked the oc­ca­sion, say­ing the at­tack “shook our Re­pub­lic to its core.”

“We must nev­er for­get the ex­tra­or­di­nary courage of law en­force­ment of­fi­cers on Jan­u­ary 6th who stood in the breach and stared down the in­sur­rec­tion­ists to pro­tect the Capi­tol, the Con­gress and the Con­sti­tu­tion,” the Cal­i­for­nia law­mak­er said in a state­ment.

Her suc­ces­sor, De­mo­c­ra­t­ic Leader Ha­keem Jef­fries echoed her sen­ti­ment, say­ing the “Amer­i­can peo­ple must nev­er be al­lowed to the for­get the events” of Jan. 6. He added that “his­to­ry will al­ways re­mem­ber the at­tempt­ed in­sur­rec­tion and we will nev­er al­low the vi­o­lence that un­fold­ed in plain sight to be white­washed.”