Which means bad actors can easily penetrate unmanned border areas and get into the US.
From the story here:
Since late summer, 27 men from Ghana walked to Manitoba from the United States, Yeboah said. Two lost all their fingers to frostbite in December and nearly froze to death.
More than 7,000 refugee applicants entered Canada in 2016 through land ports of entry from the United States, up 63 percent from the previous year, according to Canada Border Services Agency (CBSA).
Over 2,000 more entered "irregularly" during a similar time period, without official authorization, such as across unmonitored fields.
Four hundred and thirty asylum seekers crossed Manitoba's border irregularly in the first nine months of 2016-17, up from 340 the entire previous year, CBSA said. ...
In Quebec, 1,280 refugee claimants irregularly entered between April 2016 and January 2017, triple the previous year's total.
In British Columbia and Yukon, 652 people entered Canada irregularly in 2016, more than double the previous year.
More of these people would enter at border crossings, advocates say, if Canada didn't have a policy of turning many of them away when they do.