Instructions in more recent resolutions replace instructions in older resolutions, Teribus. The resolutions that instruct the US to honor its commitment to the sovereignty, territorial integrity and political independence of Iraq are more recent than the one that authorized member nations to use all means necessary (etc.). (Carol)

That's a bit of misinformation. Nearly all resolution regarding Iraq recall the old resolutions explicitly

Let's go to UNSCR 687

Conscious of the need to take the following measures acting under Chapter VII [the one about using armed force] of the Charter,

      1.   Affirms all thirteen resolutions noted above, except as expressly changed below...


Let's go to 1441. It starts

Recalling all its previous relevant resolutions, in particular its resolutions 661(1990) of 6 August 1990, 678 (1990) of 29 November 1990, 686 (1991) of 2 March1991, 687 (1991) of 3 April 1991, 688 (1991) of 5 April 1991, 707 (1991) of 15August 1991, 715 (1991) of 11 October 1991, 986 (1995) of 14 April 1995, and1284 (1999) of 17 December 1999, and all the relevant statements of its President,
...
Recalling that its resolution 678 (1990) authorized Member States to use all necessary means to uphold and implement its resolution 660 (1990) of 2 August 1990 and all relevant resolutions subsequent to resolution 660 (1990) and to restore international peace and security in the area...

New resolutions quite often do not replace old resolutions.

Wolfgang