WASHINGTON, July 29 - US President Donald Trump's most divisive nominee for a senior Pentagon post to date is expected to face a contentious Senate nomination hearing on Thursday, with Democratic lawmakers likely to grill him over remarks they deem Islamophobic.Anthony Tata, a retired Army brigadier general and ardent defender of Trump on Fox News, would hold the most senior policy position in the Pentagon if confirmed. Tata has falsely portrayed former President Barack Obama as a Muslim and accused him of being a "terrorist leader" working to benefit Iran, according to now-deleted Twitter posts seen by Reuters.The White House said it stands by Tata's nomination to fill the position of undersecretary of defense for policy."Anthony Tata is a distinguished public servant whose career has provided him with planning, policy, and operational experience both at home and abroad," White House spokesman Judd Deere said in a statement.Tata did not immediately respond to a request for comment on his deleted Twitter posts.Tata has extensive US military knowledge after serving for nearly three decades, including in a senior role in Afghanistan. However, current and former US defense officials say he has little knowledge of Asia, at a time when Defense Secretary Mark Esper is trying to focus on competition with China.Tata will appear before the Senate Armed Services Committee, whose Democratic members have signaled they would oppose his nomination.Democratric Senator Elizabeth Warren called Tata "by far Trump's most unqualified & ill-suited senior defense nominee – a high bar." She said in a statement that "an Islamophobic conspiracy theorist who called President Obama a 'terrorist leader' should not be #3 at the Pentagon."While Republican support for Tata is unclear, the Republican chair of the committee, Senator Jim Inhofe, decided to move forward with a confirmation hearing. Republican Senator Kevin Cramer has said he plans to oppose Tata's nomination unless the Pentagon makes changes to an unrelated policy issue.