Look for another identifier besides color such as a stripe or rib on one of the two other wires. That will be the Neutral wire. Make sure it connects to the Wide blade on the plug.
Is this because it is AC? No, if it isn't so identified, you are dealing with a cheap knockoff pigtail that probably belongs in the waste bin. In the 120V single phase world, Neutral is effectively at ground potential, therefore if you touch it, you shouldn't get shocked. Hot while alternating isn't at ground potential and so the voltage is alternating between +120V and -120V (RMS, actual voltage peak ±170V), making you the conductor if you connect the hot wire to the dishwasher chassis and you touch it and ground. If the neutral connects to ground in the dishwasher, you've just connected up a dead short.
As this is for a dishwasher, neutral must connect to neutral and hot to hot, any mess-up here is going to be ugly. The only other method is to use an ohmmeter to trace which wire is attached to which blade. Normally narrow blade hot, wide blade neutral and ground pin to ground. If there is no difference in blade widths, then use the socket chart below to figure out which blade is Hot and Neutral from its position and attach the wire to the appropriate terminal in the appliance.
There is only one instance where the connections could be considered even remotely "interchangeable" and that is on a double insulated device where neutral is totally and completely isolated from ground.
NEMA socket listing with blade width and "polarity". Note that NEMA 5-15 and 5-20 can be installed with the ground prong up (coat hanger excluder mode) so right and left slot position is relative.
National Electrical Code 2014
Chapter 4 Equipment for General Use
Article 400 Flexible Cords and Cables
II. Construction Specifications
400.22 Grounded-Conductor Identification. One conductor of flexible cords that is intended to be used as a grounded circuit conductor shall have a continuous marker that readily distinguishes it from the other conductor or conductors. The identification shall consist of one of the methods indicated in 400.22(A) through (F).
(A) Colored Braid. A braid finished to show a white or gray color and the braid on the other conductor or conductors finished to show a readily distinguishable solid color or colors.
(B) Tracer in Braid. A tracer in a braid of any color contrasting with that of the braid and no tracer in the braid of the other conductor or conductors. No tracer shall be used in the braid of any conductor of a flexible cord that contains a conductor having a braid finished to show white or gray.
(C) Colored Insulation. A white or gray insulation on one conductor and insulation of a readily distinguishable color or colors on the other conductor or conductors for cords having no braids on the individual conductors. For jacketed cords furnished with appliances, one conductor having its insulation colored light blue, with the other conductors having their insulation of a readily distinguishable color other than white or gray.
(D) Colored Separator. A white or gray separator on one conductor and a separator of a readily distinguishable solid color on the other conductor or conductors of cords having insulation on the individual conductors integral with the jacket.
(E) Tinned Conductors. One conductor having the individual strands tinned and the other conductor or conductors having the individual strands untinned for cords having insulation on the individual conductors integral with the jacket.
(F) Surface Marking. One or more ridges, grooves, or white stripes located on the exterior of the cord so as to identify one conductor for cords having insulation on the individual conductors integral with the jacket.
Most ordinary surge protectors are designed to protect against large incoming surges only. That is surges large enough to cause permanent damage to equipment. They are not intended to prevent mere flickering of lights.
Many (maybe most) of them provide only one-time protection against large surges (e.g. lightning strikes nearby)
It is very unlikely that a typical home/office surge protector will provide the benefit you seek.
The relevant Wikipedia article says:
A surge protector attempts to limit the voltage supplied to an electric device by either blocking or shorting to ground any unwanted voltages above a safe threshold.
The standard let-through voltage for 120 V AC devices is 330 volts
MOVs have finite life expectancy and "degrade" when exposed to a few large transients, or many more smaller transients.
Other types of protective device can be more durable, but they still might not prevent lights from flickering.
Best Answer
You can try a large capacitor at the proper rated voltage, at least 250 if your device operates at 120 volts. Connect it across the line ahead of the device.
The other option is an isolation transformer between the device and the main line which can help absorb spikes.
Good luck!