Obama: We Don't Have All Facts in Syria President addresses Syria, Boston, Guantanamo in press conference By Kevin Spak, Newser User Posted Apr 30, 2013 10:49 AM CDT 53 comments Comments President Barack Obama arrives to answers questions during his new conference in the Brady Press Briefing Room of the White House, April 30, 2013. (AP Photo/Pablo Martinez Monsivais) (Newser) – The US is pretty sure someone has used chemical weapons in Syria—but it's not sure who, President Obama revealed at a White House press conference today, at which he invited reporters to ask him questions on whatever they pleased. "What we now have is evidence that chemical weapons have been used in Syria," Obama said, according to the Guardian's liveblog. "We don't know how they were used, when they were used, who used them." He said he wanted to avoid "rushing to judgment without hard effective evidence." Obama also said that, while chemical weapon use is indeed a "game-changer," that didn't necessarily mean war. "By game-changer I mean we would have to rethink the range of options that are available to us." Other tidbits from the press conference: When asked about the hunger strike at Guantanamo Bay, Obama promised to try again to close the prison. "It is not a surprise to me that we've got problems in Guantanamo," he said. "I'm gonna go back at this. I'm going to reengage with Congress." Obama defended authorities for not catching all the warning signs about one of the alleged Boston Marathon bombers. "It's not like the FBI did nothing," Obama said, according to WLWT, pointing out that they both investigated and interviewed Tamerlan Tsarnaev. He said he was "very proud" of Jason Collins, the now openly gay NBA player, saying it was "a great thing" for gay young people "to see a role model like that." Further, "this is just one more step in the recognition that we treat everybody fairly." Asked if he still had the "juice" to get his agenda passed, he joked, "Maybe I should just pack up and go home! As Mark Twain said, rumors of my demise might be a bit exaggerated at this point."