This sounds like a cultural problem, and I don't mean an Indian versus American cultural issue but instead a corporate culture issue.
In an organization with good, solid leadership, this type of behavior is discouraged. I speak from experience being in the same position as the US developers. There are several challenges that your company is going to need to overcome with some strong leadership. These all come down to collaboration:
If your developers are on the West Coast, they likely only get a few hours in the morning of productive time to meet with you. If you and the US developers aren't using this time to meet and collaborate, then you need to find a way to make this happen. Talk to your managers, both in the US and India. Let them know how you feel, but make sure you remain constructive and avoid assigning any blame. I suggest focusing on how you feel like you're kept out of the loop, and how it makes it hard for you to not only buy into the solution but also understand it.
If you meet everyday, even if it's just to talk about what you did on the weekend, then both offices will feel more like part of a larger team. My guess, based on your description, is that your team and the US team are meeting in respective conference rooms. If each workstation isn't equipped with a headset and a web-cam, start by making sure everyone has access to technology for video calls. This allows you to collaborate individually with other developers in the US office, one on one.
Use Video Calls Instead of Chat:
Also, try to avoid chat. This is one I still struggle with, but in my Skype profile, it says "Just call me! Don't chat me as I might not see it.". Don't get me wrong, I love chat. I build chat software, but chat has its place, and it's not really that great for collaboration on topics that may involve some back and forth debate. It's easy to "disconnect" in chat and forget that you're talking to a real human being, and since there's no body language, something you type can be easily misconstrued.
If you don't have a camera, find one of your more laid back US colleagues and invite him or her to the conference room, alone, just the two of you. Start small. Commit to once per week, and then move forward from there.
Remember The Language Barrier:
American English and Indian English is drastically different. The first time a colleague in India said he "had a doubt about the code" I honestly got a little offended because in India a "doubt" is a question whereas in the US it means you don't think something will work. ;) Years later, I find myself using that terminology myself. ;) I'm sure my colleagues in India have been equally baffled by things I've said or that our US colleagues have said.
The cool thing about the video calls is you really get to know someone, even 8000 miles away. You can't do that in an "us vs them" meeting in the conference rooms...
Consider Moving On:
Times are changing, and with that management and leadership techniques must evolve. Sometimes leaders come from the freshers themselves or from mid-level employees. So, start small. Try to bridge the communication gap yourself and see if you can lead the leaders into supporting this change.
Ultimately, if management doesn't support you, then it may be time to consider finding another place to work. There are places out there that have figured this out!