Following yesterday's stark warning by the militant "black power" organization, the New Black Panther Party, which warned it would arrive in Cleveland packing firearms for self-defense ahead of the republican convention, we were curious how long it would take the various US authorities to admit that the upcoming Republican and Democratic conventions will be ground zero for the next round in escalating US violence. The answer, it turned out, was just about 24 hours.

Earlier today, Homeland Security Secretary Jeh Johnson and FBI Director James Comey told lawmakers, that they are preparing their agencies for the "possibility of violence, both from unruly demonstrators and terrorists", at the upcoming Republican and Democratic nominating conventions.

In what could end up being a self-fulfilling prophecy, Jeh Johnson, speaking before the House Homeland Security Committee, said he was concerned that demonstrations at the events could get out of hand.

"I am concerned about the prospect of demonstrations getting out of hand," Johnson told members of the House Homeland Security Committee at a hearing on terrorist threats. "I am concerned about the possibility of violence."

Johnson said he will travel to Cleveland on Friday to inspect security preparations at and around the convention site. The convention is scheduled to begin Monday and run through Thursday night at the Quicken Loans Arena.

Johnson said he also will go to Philadelphia next week to inspect security there in advance of the Democratic National Convention, which begins July 25.

"There will be a lot of security and a lot of preparation at both sites," Johnson said, adding that federal officials have been planning security for the events for a year.

In an interview with Reuters following his testimony, Johnson said he knew of no specific or credible threat to either convention but that it was important to be prepared.

Secret Service Director Joseph Clancy told USA TODAY much the same, saying on Tuesday that no specific or credible threats to the conventions have been identified. However, he also confirmed that security planning for the Republican convention includes preparing for worst-case scenarios such as the ambush in Dallas in which a lone gunman shot and killed five police officers.

He said protesters have the constitutional right to voice their opinions and that right will be respected. He said there will be roped-off areas for demonstrators near the Cleveland arena. Considering that an admittedly “virulently racist and anti-Semitic organization whose leaders have encouraged violence against whites, Jews and law enforcement officers" will be present, that sounds like a prudent idea.

According to Johnson, the Department of Homeland Security would send more than 3,000 personnel to each convention.

As extensively documented here previously, recent clashes between attendees and protesters at rallies for presumptive Republican presidential nominee Donald Trump have led to physical assaults and arrests.

The Republican National Convention being held July 18-21 in Cleveland and the Democratic National Convention in Philadelphia from July 25-28 follow a string of high-profile shootings.

Comey told the committee that the Federal Bureau of Investigation was monitoring the threat of violence at the conventions "very, very carefully."

"Anytime there is a national spotlight on a political event in the United States, there is a risk that groups that aspire to do just that, engage in acts of domestic terrorism, will be attracted," Comey said.

It goes without saying, that if anyone wished to discredit Donald Trump at what will be the most watched Republican political event of the year, an act of "domestic terrorism", ad hoc or scripted, would be precisely the way to achieve that.