What Donald Trump is doing is serving the polluters and serving a narrow group of ideological interests. That's not leadership. That's abdication of responsibility, and this step does not make America first. It makes America last.

As the saying goes, I have big heels to fill.

We owe our troops the opportunity to serve in the best-planned, best-equipped, and best-led military force in the world, and we owe them the peace of mind that comes from knowing that they and their families will be taken care of if they sacrifice life, limb or the ability to sleep without war's nightmares. We owe them not just thanks and best wishes, but action, and action in our nation's capital.

The agreement is fundamentally that we want to try to resolve this. The agreement is that ISIL is a threat to everybody, and we need to come together to find a way to fight ISIL. The agreement is that we want to save Syria, keep it unified, keep it secular. So surely in those very fundamental principles on which we could agree.

There's an agreement that Syria should be a unified country, united; that it needs to be secular; that ISIL needs to be taken on; and that there needs to be a managed transition, but there is a difference obviously in what that means and what that outcome may or may not be.

We need to put our faith and trust in the people on the frontlines -- and back it up with real resources. We need to make sure first defenders have the gear and support they need, and the benefits and protections they've earned. With new technology and ingenuity, by doing more to sustain our first defenders and calling on Americans to do more for their country, we can make our country stronger, safer, and more secure.

I think, all in all, the Obama administration and what President Obama has focused on has lived up to our need to protect American interests, to live our values and assert our values, and to stand up for future generations.