PARIS >> President Barack Obama defended his willingness to undertake climate talks in the midst of a war in Syria, saying it was “because this one trend, climate change, affects all trends.”

If global temperatures continue to increase at their current pace, if sea levels continue to rise and weather patterns continue to shift, much of the United States’ military and other spending would have to be devoted to dealing with those changes, Obama said at a news conference today in Paris, where he was attending the climate talks.

Earlier in the day, at a meeting with the leaders of five island nations extending from Barbados to Papua New Guinea, Obama, whose first two bilateral meetings in Paris were with the leaders of China and India, said that even small dots on the map deserve to be heard in international climate talks.

“I am an island boy,” Obama said, referring to his upbringing in Hawaii and Indonesia. “Some of their nations could disappear entirely, and as weather patterns change, we might deal with tens of millions of climate refugees in the Asia-Pacific region.”

Referring to the Islamic State, Obama also said that, despite repeated meetings with President Vladimir Putin of Russia, “I don’t think you should be under any illusions now that Russia will start targeting only ISIL targets.”

The Russians have been deeply invested in propping up the government of President Bashar Assad of Syria, Obama said, adding that their commitment was not going to change anytime soon.

But he added that weeks of Russian airstrikes in the region had not led to substantial changes in the Syrian conflict, and said that at some point Putin would recognize that he did not want to be involved in another quagmire, Obama said.

Obama also dismissed concerns that Republicans would be able to block the United States from fulfilling its financial pledges to help developing nations transition their economies so that they are less dependent on fossil fuels. Republicans in Congress have pledged to block such spending.

“This is not just one slug of funding that happens in one year,” Obama said. “This is multiyear commitments that in many cases are already embedded in a whole range of programs around the world. And my expectation is that we absolutely will be able to meet our commitments.”

The climate conference cannot simply serve the interests of the most powerful, Obama said, but should also serve the most vulnerable. And to do that, he said, the agreement must be both transparent and subject to periodic reviews.

There is scientific consensus that limits on growth in carbon emissions, promised by nations at the Paris conference, will not be enough to prevent dire effects of climate change, which may include the disappearance of some island nations.

Obama administration officials have expressed hope that, as energy technology and climate awareness improves, nations may to agree to more ambitious limits in the future.

Obama and members of his administration also met with President Recep Tayyip Erdogan of Turkey at the residence of the U.S. ambassador here, a small palace that once served as the home of Edmond James de Rothschild.

Even though the two had met two weeks ago at the Group of 20 summit meeting in Antalya, Turkey, Obama said another meeting was warranted in light of recent events in Syria and the shooting down of a Russian fighter plane by Turkey.

“I want to be very clear: Turkey is a NATO ally,” Obama said. “Along with our allies, the United States supports Turkey’s right to defend itself and its airspace and its territory. And we’re very much committed to Turkey’s security and its sovereignty.”

Obama said he and Erdogan discussed how to ease tensions between Russia and Turkey, to address the threat posed by the Islamic State and to bring about a political resolution in Syria. Obama also praised Turkey, which is estimated to have taken in more than one million Syrians, for its “extraordinary generosity” in its support of refugees.

In his own remarks, Erdogan said the two leaders had discussed the Islamic State, also known as ISIS; establishing a transitional government in Syria; protecting the lives of Syrians of Turkish descent; and the recent tensions between Russia and Turkey.

“We want peace to prevail at all costs,” Erdogan said.

Even before the shooting down of the Russian jet, which Turkey said had been in its airspace, Turkish officials were angry with Russia for bombing villages of ethnic Turkmen in Syria, as well as for Moscow’s continued support for Assad.

“We know that where the Turkmens are present, there’s no Daesh presence or ISIS presence,” Erdogan said, using the Arabic acronym for the Islamic State. “In the last few weeks, more than 500 civilians were killed, so we would like to see the resolution of that problem as soon as possible as well.”

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