Sen. Tom Cotton (R-Ark.) said Monday morning that he is putting a hold on three of President Obama’s ambassadorial nominees until the administration shows it is taking steps to punish Secret Service staff involved in leaking unflattering information about a lawmaker. “This was apparently a violation of law, and absolutely shocking conduct,” Cotton said in an interview. “The executive branch all the way up to the West Wing needs to treat this with the seriousness it requires.” Cotton called on Homeland Security Secretary Jeh Johnson to “personally attend” to disciplining top Secret Service leaders — specifically including new Director Joseph...