What does "waiting out/grinding down their critics" mean?


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It was only in May that Mr. Kushner had his security clearance restored after months of questions about whether he was in peril in the investigation by the special counsel, Robert S. Mueller III, into the Trump campaign’s ties to Russia. Mr. Mueller’s investigators have not publicly cleared Mr. Kushner, and Mr. Kushner’s advisers issued misleading statements that indicated his clearance had been fully restored, when in fact he was still awaiting that status.

But he and his wife are still ramping up their profiles, ready again for a more public stage to pursue their projects after waiting out — and in some cases grinding down — their critics.

“I think they felt in some ways when things escalated that they thought it was best to keep a lower profile and hone in on their specific policy areas,” said Sarah Huckabee Sanders, the White House press secretary.