Apparently, a new president can unsign this treaty. (This is not a
legal article, but it seems accurate in it's particulars)
http://dailysignal.com/2015/01/27/firearms-industry-thinks-un-arms-trade-treaty-signed-obama-administration/From 12/2014:
Most recently, the omnibus government funding bill passed by the Congress earlier this month contained new prohibitions on the administration using any funds to implement the conventional arms treaty. Under U.N. procedures the U.S. would be liable for 22 percent of the budget for the ATT secretariat, the body that will oversee its implementation.
In October 2013, 50 U.S. senators signed a letter to President Obama pledging not to give advice and consent to the ATT. In order for a treaty to be ratified, no more than 33 senators can oppose it.In cases where the Senate refuses to ratify a treaty, the executive branch may “unsign” it, notifying its depository that the U.S. does not intend to become a party, and that it has no legal obligation arising from its original signing.
President George W. Bush took that step in 2002 in the case of the treaty that established the International Criminal Court. (In contrast, Bush a year earlier announced the U.S. would not comply with the Kyoto Protocol on climate change, but he did not formally “unsign” it. The Clinton-era Kyoto signature remains in place.)Not only is this treaty in direct conflict with the 2d A, like others of it's ilk, it clearly gives away degrees of our National sovereignty to the UN, which obviously should NEVER happen. Signing such agreements by a president or ratification by a senate is also (to me) in clear violation of their oaths of office to preserve, protect and defend the constitution of the US.
One would think this is the kind of thing Pres Trump would unsign as soon as he has time to look it all over. He stood with the NRA in laying out his platform and earned their endorsement as a result.