Gooner
Pit League Fantasy Football Commissioner
Here's a good breakdown of the implications of each path Trump & Co. could take in combatting the lawsuit: LINK
Ultimately, Clifford's suit could back the President into a corner. The Supreme Court's precedent in Clinton v. Jones held that the president does not have immunity from a civil lawsuit for acts performed before he assumed office. While that case was brought in federal court, the same rationale would likely apply to state court in a case like this.
If so, then the President, as the named defendant in Clifford's lawsuit, would be forced to respond to her complaint, and potentially deposed, which is the last thing Trump would want to do. (Remember that President Bill Clinton was caught lying in a deposition in a civil suit for sexual harassment by Paula Jones -- and perjury was one of the articles of impeachment brought against him.)
And choosing not to respond at all would result in a default judgment -- meaning that Clifford would win simply because her claims are not contested -- leaving her able to discuss her version of the story in detail with no legal consequences.